CVE-2026-25210

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.

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.

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.

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, 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, 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)

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, 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, 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)

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-2026-25210 in the expat package for Root:Debian:11. Multiple fixed versions available.

Root has patched CVE-2026-25210 in the expat package for Root:Debian:12. Multiple fixed versions available.

Root has patched CVE-2026-25210 in the rootio-expat package for Root:Debian:13. Multiple fixed versions available.

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.

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.

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.

• Fix CVE-2026-25210: integer overflow in doContent tag buffer reallocation

• Fix CVE-2026-25210: integer overflow in doContent tag buffer reallocation

• Fix CVE-2026-25210: integer overflow in doContent tag buffer reallocation

• CVE-2026-25210: fix integer overflow in tag buffer reallocation in doContent function

• CVE-2026-25210: fix integer overflow in tag buffer reallocation in doContent function

• Fix CVE-2026-25210: integer overflow in doContent tag buffer reallocation

• CVE-2026-25210: fix integer overflow in tag buffer reallocation in doContent function

• SECURITY UPDATE: integer overflow in doContent tag buffer reallocation.
  • debian/patches/CVE-2026-25210.patch: add overflow check for tag buffer reallocation
  • CVE-2026-25210

• SECURITY UPDATE: integer overflow in doContent tag buffer reallocation.
  • debian/patches/CVE-2026-25210.patch: add overflow check for tag buffer reallocation
  • CVE-2026-25210

• CVE-2026-25210: fix integer overflow in tag buffer reallocation in doContent

• SECURITY UPDATE: integer overflow in doContent tag buffer reallocation.
  • debian/patches/CVE-2026-25210.patch: add overflow check for tag buffer reallocation
  • CVE-2026-25210

• CVE-2026-25210: fix memory corruption via integer overflow in doContent function during tag buffer reallocation

• CVE-2026-25210: fix memory corruption via integer overflow in doContent function during tag buffer reallocation

• SECURITY UPDATE: Improve determination of buffer size bufSize in function doContent
  • debian/patches/CVE-2026-25210.patch: fix integer overflow in doContent tag buffer reallocation
  • CVE-2026-25210

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)