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.
Problem types
CWE-191 Integer Underflow (Wrap or Wraparound)
Product status
0.017 (custom) before 0.031
Timeline
| 2026-05-12: | Issue reported. |
| 2026-05-13: | Crypt-Argon2 0.031 released with fix. |
References
www.openwall.com/lists/oss-security/2026/05/13/4
github.com/...92eac03ce63d541e0ead7ea5a89b9b67ce0c0e64.patch
metacpan.org/release/LEONT/Crypt-Argon2-0.031/changes