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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Leont | Crypt\ | >= 0.017, < 0.031, \ |
Related Weaknesses (CWE)
References
- https://github.com/Leont/crypt-argon2/commit/92eac03ce63d541e0ead7ea5a89b9b67ce0Patch
- https://metacpan.org/release/LEONT/Crypt-Argon2-0.031/changesRelease Notes
- http://www.openwall.com/lists/oss-security/2026/05/13/4Mailing ListThird Party Advisory
FAQ
What is CVE-2026-8463?
CVE-2026-8463 is a vulnerability with a CVSS score of 5.3 (MEDIUM). 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 ...
How severe is CVE-2026-8463?
CVE-2026-8463 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-8463?
Check the references section above for vendor advisories and patch information. Affected products include: Leont Crypt\.