jetperch/pymonocypher · Security
pymonocypher: Potential heap buffer overflow on nb_blocks in argon2i_32 when provided buffer is too small
- GHSA ID
- GHSA-8f95-v3jq-cj86
- CVE ID
- CVE-2026-53720
- Severity
- medium
- Published
- Updated
- CVSS v4
- 5.1 · CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
Description
Impact
The argon2i_32 implementation does not check the nb_blocks size. If the caller does not provide a sufficiently large buffer based on the API contract, then argon2i_32 will write past the end of the buffer and possibly corrupt the heap.
Patches
Fixed in 4.0.2.8, which now verifies that nb_blocks is large enough. See 90ff5b1.
Workarounds
Provide a correctly sized nb_blocks buffer.
pymonocypher thanks Haris (hextheshadow) for the vulnerability report, details, and recommended fix.
CWEs
- CWE-122 · Heap-based Buffer Overflow
- CWE-787 · Out-of-bounds Write
- CWE-1284 · Improper Validation of Specified Quantity in Input