CPANSA-Crypt-Argon2-2026-8463: Crypt-Argon2 vulnerability

Publisher giterlizzi Document category csaf_security_advisory
Initial release date 2026-05-13T00:00:00 Engine CSAF Perl Toolkit 0.26
Current release date 2026-05-13T00:00:00 Build Date
Current version 1 Status final
CVSS v3.1 Base Score 5.3 Severity
Original language Language en
Also referred to

Vulnerability Description

Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input. The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte. A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.

Vulnerabilities

CVE-2026-8463

Vulnerability Description

Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input.

The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte.

A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.

Weakness CWE-126 : Buffer Over-read

Product status

Known affected
Product Score
Crypt-Argon2 greater than or equal 0.017 and less than 0.031
CVSS Version CVSS Vector CVSS Base Score CVSS Base Severity
3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L 5.3 Medium
Fixed

giterlizzi

Namespace: https://github.com/giterlizzi/

gdt@cpan.org

References

Revision history

Version Date of the revision Summary of the revision
1 Wed May 13 00:00:00 2026 First release

Sharing rules

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