CVE-2026-24515

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.

expat is a stream-oriented XML parser library written in C. expat excels with files too large to fit RAM, and where performance and flexibility are crucial.

Security Fix(es):

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.(CVE-2026-24515)

expat is a stream-oriented XML parser library written in C. expat excels with files too large to fit RAM, and where performance and flexibility are crucial.

Security Fix(es):

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.(CVE-2026-24515)

expat is a stream-oriented XML parser library written in C. expat excels with files too large to fit RAM, and where performance and flexibility are crucial.

Security Fix(es):

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.(CVE-2026-24515)

expat is a stream-oriented XML parser library written in C. expat excels with files too large to fit RAM, and where performance and flexibility are crucial.

Security Fix(es):

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.(CVE-2026-24515)

In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize because there is no integer overflow check for tag buffer reallocation.(CVE-2026-25210)

expat is a stream-oriented XML parser library written in C. expat excels with files too large to fit RAM, and where performance and flexibility are crucial.

Security Fix(es):

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.(CVE-2026-24515)

expat is a stream-oriented XML parser library written in C. expat excels with files too large to fit RAM, and where performance and flexibility are crucial.

Security Fix(es):

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.(CVE-2026-24515)

In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize because there is no integer overflow check for tag buffer reallocation.(CVE-2026-25210)

Root has patched CVE-2026-24515 in the expat package for Root:Debian:11. Multiple fixed versions available.

Root has patched CVE-2026-24515 in the expat package for Root:Debian:12. Multiple fixed versions available.

Root has patched CVE-2026-24515 in the rootio-expat package for Root:Debian:13. Multiple fixed versions available.

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.

• CVE-2026-24515: fix NULL pointer dereference in XML_ExternalEntityParserCreate

• SECURITY UPDATE: XML_ExternalEntityParserCreate does not copy unknown encoding handler user data
  • debian/patches/CVE-2026-24515.patch: Fix a null pointer dereference in the XML parser caused by the failure to copy user data for unknown encoding handlers
  • CVE-2026-24515

• CVE-2026-24515: make XML_ExternalEntityParserCreate copy unknown encoding handler user data

• CVE-2026-24515: make XML_ExternalEntityParserCreate copy unknown encoding handler user data

• CVE-2026-24515: make XML_ExternalEntityParserCreate copy unknown encoding handler user data

• SECURITY UPDATE: Make XML_ExternalEntityParserCreate copy unknown encoding handler user data
  • debian/patches/CVE-2026-24515.patch: copy unknown encoding handler user data and add tests to cover effect
  • CVE-2026-24515

• SECURITY UPDATE: XML_ExternalEntityParserCreate failure to copy the encoding handler data can cause a NULL dereference.
  • debian/patches/CVE-2026-24515.patch: Make XML_ExternalEntityParserCreate copy unknown encoding handler user data
  • CVE-2026-24515

• CVE-2026-24515: Fix a null pointer dereference in the XML parser caused by the failure to copy user data for unknown encoding handlers

• CVE-2026-24515: Fix a null pointer dereference in the XML parser caused by the failure to copy user data for unknown encoding handlers

• CVE-2026-24515: Fix a null pointer dereference in the XML parser caused by the failure to copy user data for unknown encoding handlers

• CVE-2026-24515: Fix a null pointer dereference in the XML parser caused by the failure to copy user data for unknown encoding handlers

• CVE-2026-24515: Fix a null pointer dereference in the XML parser caused by the failure to copy user data for unknown encoding handlers

• CVE-2026-24515: fix NULL pointer dereference in XML_ExternalEntityParserCreate

• SECURITY UPDATE: XML_ExternalEntityParserCreate failure to copy the encoding handler data can cause a NULL dereference (CWE-476) from external entities that declare use of an unknown encoding. The expected impact is denial of service.
  • debian/patches/CVE-2026-24515.patch: Make XML_ExternalEntityParserCreate copy unknown encoding handler user data
  • CVE-2026-24515

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data. (CVE-2026-24515) In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize because there is no integer overflow check for tag buffer reallocation. (CVE-2026-25210)

These are all security issues fixed in the expat-2.7.4-1.1 package on the GA media of openSUSE Tumbleweed.

This update for expat fixes the following issues:

• CVE-2026-24515: failure to copy the encoding handler data passed to XML_SetUnknownEncodingHandler may cause a NULL dereference (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).

This update for expat fixes the following issues:

• CVE-2026-24515: Fixed a null dereference in XML_ExternalEntityParserCreate. (bsc#1257144)
• CVE-2026-25210: Fixed an integer overflow in doContent. (bsc#1257496)

This update for expat fixes the following issues:

• CVE-2026-24515: Fixed a null dereference in XML_ExternalEntityParserCreate. (bsc#1257144)
• CVE-2026-25210: Fixed an integer overflow in doContent. (bsc#1257496)

This update for expat fixes the following issues:

• CVE-2026-24515: Fixed a null dereference in XML_ExternalEntityParserCreate. (bsc#1257144)
• CVE-2026-25210: Fixed an integer overflow in doContent. (bsc#1257496)

This update for expat fixes the following issues:

• CVE-2026-24515: Fixed a null dereference in XML_ExternalEntityParserCreate. (bsc#1257144)
• CVE-2026-25210: Fixed an integer overflow in doContent. (bsc#1257496)

This update for expat fixes the following issues:

• CVE-2026-24515: failure to copy the encoding handler data passed to XML_SetUnknownEncodingHandler may cause a NULL dereference (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).

This update for expat fixes the following issues:

• CVE-2026-24515: failure to copy the encoding handler data passed to XML_SetUnknownEncodingHandler may cause a NULL dereference (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).

This update for expat fixes the following issues:

• CVE-2026-24515: failure to copy the encoding handler data passed to XML_SetUnknownEncodingHandler may cause a NULL dereference (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).

This update for expat fixes the following issues:

• CVE-2026-24515: failure to copy the encoding handler data passed to XML_SetUnknownEncodingHandler may cause a NULL dereference (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).

This update for expat fixes the following issues:

• CVE-2025-59375: denial of service (resource consumption) caused by processing malformed small documents (bsc#1249584).
• CVE-2026-24515: NULL dereference (CWE-476) due to function XML_ExternalEntityParserCreate() failing to copy the encoding handler data passed to XML_SetUnknownEncodingHandler() from the parent to the subparser (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).
• CVE-2026-32776: NULL pointer dereference when processing empty external parameter entities inside an entity declaration value (bsc#1259726).
• CVE-2026-32777: denial of service due to infinite loop in DTD content parsing (bsc#1259711).
• CVE-2026-32778: NULL pointer dereference in setContext on retry after an out-of-memory condition (bsc#1259729).
• CVE-2026-41080: crafted XML document can cause a denial of service (bsc#1262263).
• CVE-2026-45186: denial of service via moderately sized crafted XML input (bsc#1264713).
• CVE-2026-50219: lack of handler call depth tracking for calls to XML_* functions from within handlers in cases of a policy violation (bsc#1267631).
• CVE-2026-56131: lack of handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation (bsc#1268572).
• CVE-2026-56132: heap-based buffer overflow in doProlog in xmlparse.c (bsc#1268573).
• CVE-2026-56403,CVE-2026-56404,CVE-2026-56405,CVE-2026-56406, CVE-2026-56407,CVE-2026-56408,CVE-2026-56409,CVE-2026-56410, CVE-2026-56411,CVE-2026-56412: multiple integer overflow vulnerabilities (bsc#1275115).
• CVE-2026-66046: denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function (bsc#1275732).
• CVE-2026-72522: out-of-bounds read and resultant infinite loop due to low surrogates being treated the same as high surrogates during Unicode processing (bsc#1275594).
• CVE-2026-76641: out-of-bounds read vulnerability that allows attackers to trigger memory corruption (bsc#1275915).
• CVE-2026-76956: denial of service via hash flooding attacks (bsc#1275860).
• CVE-2026-76957: lack of handler call depth tracking with custom encoding callbacks. Thus, a use- after-free can occur (bsc#1275859).
• CVE-2026-77214: out-of-bounds read due to insufficient checks in XML_ParseBuffer() (bsc#1284334).
• CVE-2026-93990: fails to validate low surrogates following high surrogates in UTF-16 input (bsc#1282347).
• CVE-2026-102633: Denial of Service via integer overflow in expat_realloc (bsc#1283493).

Update to 2.8.5 (jsc#PED-16154):

• Bug fixes:
• Fix an OOM-related memory leak on a failed overflow check
• Fix memory alignment for architectures with 128bit pointers
• Mark XML_SetHashSalt deprecated
• CMake: only add /source-charset:utf-8 when /utf-8 is not present
• lib: resolve undefined behavior from overshifting a signed int
• lib: support read-only hash table lookup with non-zero-terminated keys
• lib: use a C99 bool for ENTITY.open
• version info bumped from 13:3:12 to 13:4:12
• fix support for 2+ GiB documents (regression from 2.8.2)
• reject empty version in the XML declaration
• fix printf format for AIX
• CMake|AIX: enable EXPAT_DEV_URANDOM by default
• version info bumped from 13:2:12 to 13:3:12
• Existing API function XML_SetHashSalt is now deprecated
• because of its limitations, and its use should be
• considered a vulnerability. Please either use the new API
• function XML_SetHashSalt16Bytes (with known-high-quality
• entropy input only!) instead, or leave the derivation of
• a 16-bytes hash salt from high quality entropy to Expat's
• internal machinery (by not calling either of the two
• XML_SetHashSalt* functions).
• xmlwf: Fix a memory leak
• WASI: Fix format specifiers for 32bit WASI SDK
• Fix alignment of internal allocations for some non-amd64 architectures (e.g. sparc32); fixes up on the fix to CVE-2025-59375 (of Expat 2.7.2)
• Fix a class of…

This update for expat fixes the following issues:

• CVE-2025-59375: denial of service (resource consumption) caused by processing malformed small documents (bsc#1249584).
• CVE-2026-24515: NULL dereference (CWE-476) due to function XML_ExternalEntityParserCreate() failing to copy the encoding handler data passed to XML_SetUnknownEncodingHandler() from the parent to the subparser (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).
• CVE-2026-32776: NULL pointer dereference when processing empty external parameter entities inside an entity declaration value (bsc#1259726).
• CVE-2026-32777: denial of service due to infinite loop in DTD content parsing (bsc#1259711).
• CVE-2026-32778: NULL pointer dereference in setContext on retry after an out-of-memory condition (bsc#1259729).
• CVE-2026-41080: crafted XML document can cause a denial of service (bsc#1262263).
• CVE-2026-45186: denial of service via moderately sized crafted XML input (bsc#1264713).
• CVE-2026-50219: lack of handler call depth tracking for calls to XML_* functions from within handlers in cases of a policy violation (bsc#1267631).
• CVE-2026-56131: lack of handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation (bsc#1268572).
• CVE-2026-56132: heap-based buffer overflow in doProlog in xmlparse.c (bsc#1268573).
• CVE-2026-56403,CVE-2026-56404,CVE-2026-56405,CVE-2026-56406, CVE-2026-56407,CVE-2026-56408,CVE-2026-56409,CVE-2026-56410, CVE-2026-56411,CVE-2026-56412: multiple integer overflow vulnerabilities (bsc#1275115).
• CVE-2026-66046: denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function (bsc#1275732).
• CVE-2026-72522: out-of-bounds read and resultant infinite loop due to low surrogates being treated the same as high surrogates during Unicode processing (bsc#1275594).
• CVE-2026-76641: out-of-bounds read vulnerability that allows attackers to trigger memory corruption (bsc#1275915).
• CVE-2026-76956: denial of service via hash flooding attacks (bsc#1275860).
• CVE-2026-76957: lack of handler call depth tracking with custom encoding callbacks. Thus, a use- after-free can occur (bsc#1275859).
• CVE-2026-77214: out-of-bounds read due to insufficient checks in XML_ParseBuffer() (bsc#1284334).
• CVE-2026-93990: fails to validate low surrogates following high surrogates in UTF-16 input (bsc#1282347).
• CVE-2026-102633: Denial of Service via integer overflow in expat_realloc (bsc#1283493).

Changes for expat:

Update to 2.8.5 (jsc#PED-16154):

• Bug fixes:
• Fix an OOM-related memory leak on a failed overflow check
• Fix memory alignment for architectures with 128bit pointers
• Mark XML_SetHashSalt deprecated
• CMake: only add /source-charset:utf-8 when /utf-8 is not present
• lib: resolve undefined behavior from overshifting a signed int
• lib: support read-only hash table lookup with non-zero-terminated keys
• lib: use a C99 bool for ENTITY.open
• version info bumped from 13:3:12 to 13:4:12
• fix support for 2+ GiB documents (regression from 2.8.2)
• reject empty version in the XML declaration
• fix printf format for AIX
• CMake|AIX: enable EXPAT_DEV_URANDOM by default
• version info bumped from 13:2:12 to 13:3:12
• Existing API function XML_SetHashSalt is now deprecated
• because of its limitations, and its use should be
• considered a vulnerability. Please either use the new API
• function XML_SetHashSalt16Bytes (with known-high-quality
• entropy input only!) instead, or leave the derivation of
• a 16-bytes hash salt from high quality entropy to Expat's
• internal machinery (by not calling either of the two
• XML_SetHashSalt* functions).
• xmlwf: Fix a memory leak
• WASI: Fix format specifiers for 32bit WASI SDK
• Fix alignment of internal allocations for some non-amd64 architectures (e.g. sparc32); fixes up on the fix to CVE-2025-59375 (of Expat 2.7.2) …

This update for expat fixes the following issues:

• CVE-2025-59375: denial of service (resource consumption) caused by processing malformed small documents (bsc#1249584).
• CVE-2026-24515: NULL dereference (CWE-476) due to function XML_ExternalEntityParserCreate() failing to copy the encoding handler data passed to XML_SetUnknownEncodingHandler() from the parent to the subparser (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).
• CVE-2026-32776: NULL pointer dereference when processing empty external parameter entities inside an entity declaration value (bsc#1259726).
• CVE-2026-32777: denial of service due to infinite loop in DTD content parsing (bsc#1259711).
• CVE-2026-32778: NULL pointer dereference in setContext on retry after an out-of-memory condition (bsc#1259729).
• CVE-2026-41080: crafted XML document can cause a denial of service (bsc#1262263).
• CVE-2026-45186: denial of service via moderately sized crafted XML input (bsc#1264713).
• CVE-2026-50219: lack of handler call depth tracking for calls to XML_* functions from within handlers in cases of a policy violation (bsc#1267631).
• CVE-2026-56131: lack of handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation (bsc#1268572).
• CVE-2026-56132: heap-based buffer overflow in doProlog in xmlparse.c (bsc#1268573).
• CVE-2026-56403,CVE-2026-56404,CVE-2026-56405,CVE-2026-56406, CVE-2026-56407,CVE-2026-56408,CVE-2026-56409,CVE-2026-56410, CVE-2026-56411,CVE-2026-56412: multiple integer overflow vulnerabilities (bsc#1275115).
• CVE-2026-66046: denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function (bsc#1275732).
• CVE-2026-72522: out-of-bounds read and resultant infinite loop due to low surrogates being treated the same as high surrogates during Unicode processing (bsc#1275594).
• CVE-2026-76641: out-of-bounds read vulnerability that allows attackers to trigger memory corruption (bsc#1275915).
• CVE-2026-76956: denial of service via hash flooding attacks (bsc#1275860).
• CVE-2026-76957: lack of handler call depth tracking with custom encoding callbacks. Thus, a use- after-free can occur (bsc#1275859).
• CVE-2026-77214: out-of-bounds read due to insufficient checks in XML_ParseBuffer() (bsc#1284334).
• CVE-2026-93990: fails to validate low surrogates following high surrogates in UTF-16 input (bsc#1282347).
• CVE-2026-102633: Denial of Service via integer overflow in expat_realloc (bsc#1283493).

Update to 2.8.5 (jsc#PED-16154):

• Bug fixes:
• Fix an OOM-related memory leak on a failed overflow check
• Fix memory alignment for architectures with 128bit pointers
• Mark XML_SetHashSalt deprecated
• CMake: only add /source-charset:utf-8 when /utf-8 is not present
• lib: resolve undefined behavior from overshifting a signed int
• lib: support read-only hash table lookup with non-zero-terminated keys
• lib: use a C99 bool for ENTITY.open
• version info bumped from 13:3:12 to 13:4:12
• fix support for 2+ GiB documents (regression from 2.8.2)
• reject empty version in the XML declaration
• fix printf format for AIX
• CMake|AIX: enable EXPAT_DEV_URANDOM by default
• version info bumped from 13:2:12 to 13:3:12
• Existing API function XML_SetHashSalt is now deprecated
• because of its limitations, and its use should be
• considered a vulnerability. Please either use the new API
• function XML_SetHashSalt16Bytes (with known-high-quality
• entropy input only!) instead, or leave the derivation of
• a 16-bytes hash salt from high quality entropy to Expat's
• internal machinery (by not calling either of the two
• XML_SetHashSalt* functions).
• xmlwf: Fix a memory leak
• WASI: Fix format specifiers for 32bit WASI SDK
• Fix alignment of internal allocations for some non-amd64 architectures (e.g. sparc32); fixes up on the fix to CVE-2025-59375 (of Expat 2.7.2)
• Fix a class of…

This update for expat fixes the following issues:

• CVE-2025-59375: denial of service (resource consumption) caused by processing malformed small documents (bsc#1249584).
• CVE-2026-24515: NULL dereference (CWE-476) due to function XML_ExternalEntityParserCreate() failing to copy the encoding handler data passed to XML_SetUnknownEncodingHandler() from the parent to the subparser (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).
• CVE-2026-32776: NULL pointer dereference when processing empty external parameter entities inside an entity declaration value (bsc#1259726).
• CVE-2026-32777: denial of service due to infinite loop in DTD content parsing (bsc#1259711).
• CVE-2026-32778: NULL pointer dereference in setContext on retry after an out-of-memory condition (bsc#1259729).
• CVE-2026-41080: crafted XML document can cause a denial of service (bsc#1262263).
• CVE-2026-45186: denial of service via moderately sized crafted XML input (bsc#1264713).
• CVE-2026-50219: lack of handler call depth tracking for calls to XML_* functions from within handlers in cases of a policy violation (bsc#1267631).
• CVE-2026-56131: lack of handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation (bsc#1268572).
• CVE-2026-56132: heap-based buffer overflow in doProlog in xmlparse.c (bsc#1268573).
• CVE-2026-56403,CVE-2026-56404,CVE-2026-56405,CVE-2026-56406, CVE-2026-56407,CVE-2026-56408,CVE-2026-56409,CVE-2026-56410, CVE-2026-56411,CVE-2026-56412: multiple integer overflow vulnerabilities (bsc#1275115).
• CVE-2026-66046: denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function (bsc#1275732).
• CVE-2026-72522: out-of-bounds read and resultant infinite loop due to low surrogates being treated the same as high surrogates during Unicode processing (bsc#1275594).
• CVE-2026-76641: out-of-bounds read vulnerability that allows attackers to trigger memory corruption (bsc#1275915).
• CVE-2026-76956: denial of service via hash flooding attacks (bsc#1275860).
• CVE-2026-76957: lack of handler call depth tracking with custom encoding callbacks. Thus, a use- after-free can occur (bsc#1275859).
• CVE-2026-77214: out-of-bounds read due to insufficient checks in XML_ParseBuffer() (bsc#1284334).
• CVE-2026-93990: fails to validate low surrogates following high surrogates in UTF-16 input (bsc#1282347).
• CVE-2026-102633: Denial of Service via integer overflow in expat_realloc (bsc#1283493).

Update to 2.8.5 (jsc#PED-16154):

• Bug fixes:
• Fix an OOM-related memory leak on a failed overflow check
• Fix memory alignment for architectures with 128bit pointers
• Mark XML_SetHashSalt deprecated
• CMake: only add /source-charset:utf-8 when /utf-8 is not present
• lib: resolve undefined behavior from overshifting a signed int
• lib: support read-only hash table lookup with non-zero-terminated keys
• lib: use a C99 bool for ENTITY.open
• version info bumped from 13:3:12 to 13:4:12
• fix support for 2+ GiB documents (regression from 2.8.2)
• reject empty version in the XML declaration
• fix printf format for AIX
• CMake|AIX: enable EXPAT_DEV_URANDOM by default
• version info bumped from 13:2:12 to 13:3:12
• Existing API function XML_SetHashSalt is now deprecated
• because of its limitations, and its use should be
• considered a vulnerability. Please either use the new API
• function XML_SetHashSalt16Bytes (with known-high-quality
• entropy input only!) instead, or leave the derivation of
• a 16-bytes hash salt from high quality entropy to Expat's
• internal machinery (by not calling either of the two
• XML_SetHashSalt* functions).
• xmlwf: Fix a memory leak
• WASI: Fix format specifiers for 32bit WASI SDK
• Fix a class of false positives where input should have been rejected with error XML_ERROR_ASYNC_ENTITY; regression from earlier security fix (of Expat 2.7.0) …

This update for expat fixes the following issues:

• CVE-2025-59375: denial of service (resource consumption) caused by processing malformed small documents (bsc#1249584).
• CVE-2026-24515: NULL dereference (CWE-476) due to function XML_ExternalEntityParserCreate() failing to copy the encoding handler data passed to XML_SetUnknownEncodingHandler() from the parent to the subparser (bsc#1257144).
• CVE-2026-25210: lack of buffer size check can lead to an integer overflow (bsc#1257496).
• CVE-2026-32776: NULL pointer dereference when processing empty external parameter entities inside an entity declaration value (bsc#1259726).
• CVE-2026-32777: denial of service due to infinite loop in DTD content parsing (bsc#1259711).
• CVE-2026-32778: NULL pointer dereference in setContext on retry after an out-of-memory condition (bsc#1259729).
• CVE-2026-41080: crafted XML document can cause a denial of service (bsc#1262263).
• CVE-2026-45186: denial of service via moderately sized crafted XML input (bsc#1264713).
• CVE-2026-50219: lack of handler call depth tracking for calls to XML_* functions from within handlers in cases of a policy violation (bsc#1267631).
• CVE-2026-56131: lack of handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation (bsc#1268572).
• CVE-2026-56132: heap-based buffer overflow in doProlog in xmlparse.c (bsc#1268573).
• CVE-2026-56403,CVE-2026-56404,CVE-2026-56405,CVE-2026-56406, CVE-2026-56407,CVE-2026-56408,CVE-2026-56409,CVE-2026-56410, CVE-2026-56411,CVE-2026-56412: multiple integer overflow vulnerabilities (bsc#1275115).
• CVE-2026-66046: denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function (bsc#1275732).
• CVE-2026-72522: out-of-bounds read and resultant infinite loop due to low surrogates being treated the same as high surrogates during Unicode processing (bsc#1275594).
• CVE-2026-76641: out-of-bounds read vulnerability that allows attackers to trigger memory corruption (bsc#1275915).
• CVE-2026-76956: denial of service via hash flooding attacks (bsc#1275860).
• CVE-2026-76957: lack of handler call depth tracking with custom encoding callbacks. Thus, a use- after-free can occur (bsc#1275859).
• CVE-2026-77214: out-of-bounds read due to insufficient checks in XML_ParseBuffer() (bsc#1284334).
• CVE-2026-93990: fails to validate low surrogates following high surrogates in UTF-16 input (bsc#1282347).
• CVE-2026-102633: Denial of Service via integer overflow in expat_realloc (bsc#1283493).

Update to 2.8.5 (jsc#PED-16154):

• Bug fixes:
• Fix an OOM-related memory leak on a failed overflow check
• Fix memory alignment for architectures with 128bit pointers
• Mark XML_SetHashSalt deprecated
• CMake: only add /source-charset:utf-8 when /utf-8 is not present
• lib: resolve undefined behavior from overshifting a signed int
• lib: support read-only hash table lookup with non-zero-terminated keys
• lib: use a C99 bool for ENTITY.open
• version info bumped from 13:3:12 to 13:4:12
• fix support for 2+ GiB documents (regression from 2.8.2)
• reject empty version in the XML declaration
• fix printf format for AIX
• CMake|AIX: enable EXPAT_DEV_URANDOM by default
• version info bumped from 13:2:12 to 13:3:12
• Existing API function XML_SetHashSalt is now deprecated
• because of its limitations, and its use should be
• considered a vulnerability. Please either use the new API
• function XML_SetHashSalt16Bytes (with known-high-quality
• entropy input only!) instead, or leave the derivation of
• a 16-bytes hash salt from high quality entropy to Expat's
• internal machinery (by not calling either of the two
• XML_SetHashSalt* functions).
• xmlwf: Fix a memory leak
• WASI: Fix format specifiers for 32bit WASI SDK
• Fix alignment of internal allocations for some non-amd64 architectures (e.g. sparc32); fixes up on the fix to CVE-2025-59375 (of Expat 2.7.2)
• Fix a class of…

USN-8022-1 fixed vulnerabilities in Expat. This update provides the corresponding updates for Ubuntu 24.04 LTS.

Original advisory details:

It was discovered that Expat incorrectly handled the initialization of parsers for external entities. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-24515)

It was discovered that Expat incorrectly handled integer calculations when allocating memory for XML tags. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-25210)

It was discovered that Expat, contained within the xmltok library, incorrectly handled the initialization of parsers for external entities. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-24515)

It was discovered that Expat, contained within the xmltok library, incorrectly handled integer calculations when allocating memory for XML tags. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-25210)