{"id":"CVE-2026-21900","summary":"CryptoLib Has Out-of-Bounds Read in KMC Encrypt Metadata Parsing via Flawed strtok Pattern","details":"CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. Prior to version 1.4.3, an out-of-bounds heap read vulnerability in cryptography_encrypt() occurs when parsing JSON metadata from KMC server responses. The flawed strtok iteration pattern uses ptr + strlen(ptr) + 1 which reads one byte past allocated buffer boundaries when processing short or malformed metadata strings. This issue has been patched in version 1.4.3.","aliases":["GHSA-4g6v-36fv-qcvw"],"modified":"2026-08-12T03:51:38.727719588Z","published":"2026-01-10T00:14:33.782Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-125"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21900.json"},"references":[{"type":"WEB","url":"https://github.com/nasa/CryptoLib/releases/tag/v1.4.3"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21900.json"},{"type":"ADVISORY","url":"https://github.com/nasa/CryptoLib/security/advisories/GHSA-4g6v-36fv-qcvw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-21900"},{"type":"FIX","url":"https://github.com/nasa/CryptoLib/commit/2372efd3da1ccb226b4297222e25f41ecc84821d"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/nasa/cryptolib","events":[{"introduced":"0"},{"fixed":"9ffda0ff78e8f74c58db4c181923196870e04c3e"},{"fixed":"2372efd3da1ccb226b4297222e25f41ecc84821d"}],"database_specific":{"cpe":"cpe:2.3:a:nasa:cryptolib:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"1.4.3"}],"source":["CPE_RANGE","REFERENCES"]}}],"versions":["v1.4.2","v1.4.0","v1.3.3","v1.3.2","v1.3.1","v1.3.0","v1.2.3","v1.2.2","v1.2.1","v1.2.0","v1.1.1","v1.1.0","v1.0.3"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-21900.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}