CVE-2026-58102: Crypt::OpenSSL::X509 versions before 2.1.3 for Perl allow a heap out-of-bounds read via a long certificate extension OID in hv_exts

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-13 · updated 2026-10-24
Weakness: CWE-125

Description

Crypt::OpenSSL::X509 versions before 2.1.3 for Perl allow a heap out-of-bounds read via a long certificate extension OID in hv_exts. When building the extension hash (via extensions(), extensions_by_long_name(), extensions_by_oid(), or has_extension_oid()), the code passes OBJ_obj2txt()'s return value as the hash-key length; because that value is the OID's full text length rather than the bytes written to the fixed-size buffer (129 bytes), an OID whose text is longer than the 129-byte buffer causes a read past the allocation, exposing adjacent heap memory as the returned hash key. extensions_by_name() uses the static shortname path and is not affected.

Affected products

JONASBN Crypt::Openssl::X509: before 2.1.3 — fixed in 2.1.3

How to fix

Upgrade to a fixed version: JONASBN Crypt::Openssl::X509 2.1.3. Check the vendor advisory for mitigations.

References

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