{"cve":"CVE-2026-53720","nvd":{"published":"2026-09-03T16:17:25.360","modified":"2026-09-09T21:09:13.080","status":"Deferred","description":"pymonocypher uses cython to wrap the Monocypher C library. Prior to version 4.0.2.8, 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. This issue has been patched in version 4.0.2.8.","cvss_v4":{"vector":"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","score":5.1},"cvss_v3":null,"cwes":["CWE-122","CWE-787","CWE-1284"],"references":["https://github.com/jetperch/pymonocypher/commit/90ff5b13b13b5673c372e188f482d8c172e6ab86","https://github.com/jetperch/pymonocypher/releases/tag/v4.0.2.8","https://github.com/jetperch/pymonocypher/security/advisories/GHSA-8f95-v3jq-cj86"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:52:03.409947763+00:00"},"epss":{"cve":"CVE-2026-53720","score":0.00178,"percentile":0.07386,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-8f95-v3jq-cj86","url":"https://osv.dev/vulnerability/GHSA-8f95-v3jq-cj86","summary":"pymonocypher: Potential heap buffer overflow on nb_blocks in argon2i_32 when provided buffer is too small","modified":"2026-07-13T16:42:57.702687797Z","packages":[{"ecosystem":"PyPI","name":"pymonocypher","purl":"pkg:pypi/pymonocypher","ranges":["<4.0.2.8"],"fixed":["4.0.2.8"]}]},{"id":"PYSEC-2026-3000","url":"https://osv.dev/vulnerability/PYSEC-2026-3000","summary":"pymonocypher: Potential heap buffer overflow on nb_blocks in argon2i_32 when provided buffer is too small","modified":"2026-07-13T16:33:07.802709798Z","packages":[{"ecosystem":"PyPI","name":"pymonocypher","purl":"pkg:pypi/pymonocypher","ranges":["<4.0.2.8"],"fixed":["4.0.2.8"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}