CRITICAL · 9.1

CVE-2026-59142

Data::HashMap::Shared versions before 0.14 for Perl allow an out-of-bounds read via an unvalidated arena offset and length in shm_str_copy. The attach-time validator shm_validate_header checks the he...

Vulnerability Description

Data::HashMap::Shared versions before 0.14 for Perl allow an out-of-bounds read via an unvalidated arena offset and length in shm_str_copy. The attach-time validator shm_validate_header checks the header scalars and region layout against the file size, but does not validate the array contents it then trusts. shm_str_copy does memcpy(dst, arena + off, len) with off and len read raw from the mmap'd segment and unbounded, on the each, keys, values, pop, shift, take, swap, drain and cursor paths. The get path bounds off and len separately and is not affected. A local peer that can write the backing file can leave the header valid while poisoning a record's offset and length, so iterating or draining the map copies a file-controlled offset and length out of the arena, reading adjacent memory or crashing the process.

CVSS Score

9.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
HIGH

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-59142?

CVE-2026-59142 is a vulnerability with a CVSS score of 9.1 (CRITICAL). Data::HashMap::Shared versions before 0.14 for Perl allow an out-of-bounds read via an unvalidated arena offset and length in shm_str_copy. The attach-time validator shm_validate_header checks the he...

How severe is CVE-2026-59142?

CVE-2026-59142 has been rated CRITICAL with a CVSS base score of 9.1/10. This is considered a critical vulnerability requiring immediate attention.

Is there a patch for CVE-2026-59142?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.