CVE-2025-40929

Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact

This module converts Perl data structures to JSON and vice versa. Its primary goal is to be correct and its secondary goal is to be fast. To reach the latter goal it was written in C.

Security Fix(es):

Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact(CVE-2025-40929)

This module converts Perl data structures to JSON and vice versa. Its primary goal is to be correct and its secondary goal is to be fast. To reach the latter goal it was written in C.

Security Fix(es):

Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact(CVE-2025-40929)

Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact

Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact

Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact

Cpanel::JSON::XS before version 4.40 for Perl has an integer buffer overflow causing a segfault when parsing crafted JSON, enabling denial-of-service attacks or other unspecified impact. (CVE-2025-40929)

These are all security issues fixed in the perl-Cpanel-JSON-XS-4.400.0-1.1 package on the GA media of openSUSE Tumbleweed.

This update for perl-Cpanel-JSON-XS fixes the following issues:

Changes in perl-Cpanel-JSON-XS:

• updated to 4.420.0 (4.42) see /usr/share/doc/packages/perl-Cpanel-JSON-XS/Changes

  4.42 2026-06-27 (rurban)

  • Ensure encode with a type spec hashref does not change the hashref argument (GH #240) - Fix -e docs: "written" → "read" (GH #239, reported by Ron Savage). - Fix Boolean eq overload matching undef (GH #207, reported by fd-t). Cpanel::JSON::XS::Boolean overloaded eq would match undef as equal to false because undef stringifies to "". Added defined() guard. - Fix error messages showing overloaded stringification for blessed objects (GH #191, reported by karenetheridge). Error messages now use ClassName=TYPE(addr) format, bypassing any "" overload. - Fix type_all_string overriding allow_blessed/convert_blessed (GH #175, reported by alpha6). With type_all_string + allow_blessed, blessed objects are now encoded as null (not stringified as HASH address). - Fix infinite recursion when encode is called from a "" overload (GH #128, reported by pbrthemaster). The recursion guard temporarily clears convert_blessed and allow_stringify flags on the JSON object before calling the overload, preventing re-entrant encode loops. - Fix $obj->new creating a broken object (GH #93, reported by cpansprout). When new() is called on an existing object (e.g. $json->new->new), the class name is now extracted from the object's stash rather than using the stringified reference. - Change allow_nonref default to true (GH #241, matching JSON::PP and JSON::XS 4.0+ and the insecure RFC 7159). encode and decode now accept non-reference values by default. decode_json() with an explicit 0/1 second argument still works. allow_nonref(0) to disable scalars-only for secure JSON. - Fix minor t/12_blessed.t typo. - Fix GH #112: encode large whole-number NV values without .0 on 32-bit Perl (values exceeding UV_MAX that Perl stores as float). - Fix GH #197: prefer IOK over pNOK when encoding values where IV is accurate but NV is imprecise (SvNOK not set).

• updated to 4.410.0 (4.41) see /usr/share/doc/packages/perl-Cpanel-JSON-XS/Changes

  4.41 2026-05-27 (rurban)

  • Fix BOM-shift PV-corruption SIGABRT (CVE-2026-9516) (patch by Paul Johnson) bsc#1267547
  • Fix dupkeys_as_arrayref type confusion (CVE-2026-9334) (patch by Paul Johnson) bsc#1267546
  • Fix incr_parse single-quote string delimiter (GH #245, reported by Paul Johnson)
  • Fix a one-byte out-of-bounds heap read reachable via allow_barekey on truncated input (GH #244, reported by Paul Johnson)

• updated to 4.400.0 (4.40) see /usr/share/doc/packages/perl-Cpanel-JSON-XS/Changes

  4.40 2025-09-07 (rurban)

  • Fix CVE-2025-40929 overflow with overlong numbers, fuzzing only.
  • Detect more malformed numbers, with two decimal points.
  • Pin github actions to latest @v via pinact run -u (bsc#1249331)

• updated to 4.390.0 (4.39) see /usr/share/doc/packages/perl-Cpanel-JSON-XS/Changes

  4.39 2024-12-12 (rurban) - Fix Windows -Dusequadmath (sisyphus GH #235, GH #229) - Fix inconsistent behavior between decoding escaped and unescaped surrogates, and escaped non-characters vs non-escaped non-characters. Now aligned to JSON::PP (Gavin Hayes GH #233, GH #227) - Add type_all_string tests (Bernhard Schmalhofer GH #236) - Silence UV to char cast warnings (bulk88 GH #232) - Fix MSVC preprocessor errors (bulk88 GH #232) - Fix -Wformat warnings on Windows (sisyphus GH #228) - Clarify BigInt decoding (GH #226)

This update for perl-Cpanel-JSON-XS fixes the following issues:

• CVE-2025-40929: integer buffer overflow causing a segmentation fault when parsing crafted JSON (bsc#1249331).

This update for perl-Cpanel-JSON-XS fixes the following issues:

• CVE-2025-40929: integer overflow (bsc#1249331).
• CVE-2026-9334: type confusion via duplicate object keys when dupkeys_as_arrayref is enabled (bsc#1267546).
• CVE-2026-9516: denial of service via UTF-8 BOM prefixed input when a decode filter callback throws (bsc#1267547).
• CVE-2026-110672: leak of decoded key of an object rejected for a duplicate key or a missing colon in decode_hv (bsc#1286166).
• CVE-2026-110673: stack exhaustion via nested tagged values under allow_tags in decode_tag (bsc#1286167).
• CVE-2026-110674: duplicate non-ASCII bare keys are missed, allowing type confusion under dupkeys_as_arrayref in decode_hv (bsc#1286168).
• CVE-2026-110675: malformed UTF-8 accepted in bare hash keys under allow_barekey in decode_hv (bsc#1286169).
• CVE-2026-110676: memory exhaustion by encoding exponent notation as full decimal digits under allow_bignum (bsc#1286170).
• CVE-2026-110677: array collecting duplicate key values leaked under dupkeys_as_arrayref in decode_hv (bsc#1286173).
• CVE-2026-110678: memory exhaustion by buffering incremental input past max_size in incr_parse (bsc#1286174).
• CVE-2026-110680: out-of-bounds write when a tied or shared hash grows during canonical encoding in encode_hv (bsc#1286175).
• CVE-2026-110681: parent interpreter's scalars from a parser object cloned into a new ithread (bsc#1286176).
• CVE-2026-110682: input chunking can change the decoded value of top-level numbers in incr_parse (bsc#1286177).
• CVE-2026-110684: memory leaked and overloaded objects retained when encoding values as strings in encode_stringify (bsc#1286179).
• CVE-2026-110685: decoded arguments of a tagged value leaked when its THAW method dies in decode_tag (bsc#1286180).
• CVE-2026-110686: freed filter callbacks used when a filter removes itself during decoding in decode_hv (bsc#1286181).
• CVE-2026-110687: byte-string keys misordered during canonical encoding in utf16_cmp (bsc#1286182).
• CVE-2026-110688: quadratic CPU use due to remaining buffer revalidation per value in incr_parse (bsc#1286183).

Changes for perl-Cpanel-JSON-XS:

• updated to 4.800.0 (4.80)
• Add version markers to all module files. (PR #260 demerphq)
• Use utf8n_to_uvchr on Perl 5.32 and later to avoid the deprecated utf8n_to_uvuni API. (PR #260 demerphq)
• Add schema-based validation for decoded JSON (GH #238): Cpanel::JSON::XS::Type now provides check_type($data, $schema[, $found_type]), which validates an already-decoded perl structure against a type spec built from the existing encoder building blocks (JSON_TYPE_* / json_type_arrayof / json_type_hashof / json_type_anyof), plus the new json_type_optional() for hash keys that may be absent, and short scalar type name sugar ('Str', 'Int', 'Float', 'Bool', 'Null', 'Any', and nullable 'Str?' etc.) so a schema reads as 'just a hash of keys and types', as requested. Unlike the encoder's hash type spec, a plain hashref schema is closed: unknown keys and missing required keys are reported. New $json->decode_and_validate($json_text, $schema) method decodes and croaks with all mismatches if validation fails, using decode()'s own type introspection as ground truth to avoid perl's usual dual-var/stringified-number ambiguity.
• json_type_optional() and the nullable '?' type-name suffixes ('Str?', 'Int?', 'Float?', 'Bool?') give schemas an explicit way to declare a key/value as optional instead of demanding a complete type specification for every key. The encoder now also understands json_type_optional() directly (it unwraps to the wrapped type, since encode() only ever sees keys that are actually present): the exact same type spec built for check_type()/decode_and_validate() can now be handed to encode() as-is, instead of croaking with 'no type was specified for hash key '...'' for every optional key. Encoding stays strict by default otherwise: a hash key…

It was discovered that Cpanel-JSON-XS incorrectly handled parsing certain JSON data. An attacker could possibly use this issue to cause Cpanel-JSON-XS to crash, resulting in a denial of service.