CVE-2026-53720

pymonocypher (Python bindings to the Monocypher C library) is vulnerable to a heap buffer overflow in the argon2i_32 function prior to version 4.0.2.8 . The root cause is a missing validation of the nb_blocks buffer size: if the caller supplies a buffer smaller than required by the API contract, ...

CVE-2026-53720 pymonocypher: Potential heap buffer overflow on nb_blocks in argon2i_32 when provided buffer is too small

pymonocypher uses cython to wrap the Monocypher C library. Prior to version 4.0.2.8, the argon2i32 implementation does not check the nbblocks size. If the caller does not provide a sufficiently large buffer based on the API contract, then argon2i32 will write past the end of the buffer and possib...