Vulnerability record · CVE-2026-8463 · published 13 May 2026
CVE-2026-8463: Leont crypt\ vulnerability
Leont · Crypt\
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.
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://github.com/Leont/crypt-argon2/commit/92eac03ce63d541e0ead7ea5a89b9b67ce0c0e64.patch | Patch |
| https://metacpan.org/release/LEONT/Crypt-Argon2-0.031/changes | Release Notes |
| http://www.openwall.com/lists/oss-security/2026/05/13/4 | Mailing ListThird Party Advisory |
Track CVE-2026-8463 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-8463), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.
