{"id":"CVE-2026-21900","state":"PUBLISHED","title":"CryptoLib Has Out-of-Bounds Read in KMC Encrypt Metadata Parsing via Flawed strtok Pattern","description":"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.","publishedAt":"2026-01-10T00:14:33.782Z","updatedAt":"2026-01-13T17:16:34.273Z","severity":{"score":8.2,"label":"High","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["nasa CryptoLib"],"affected":[{"vendor":"nasa","product":"CryptoLib","versions":[{"version":"< 1.4.3","status":"affected"}]}],"references":["https://github.com/nasa/CryptoLib/security/advisories/GHSA-4g6v-36fv-qcvw","https://github.com/nasa/CryptoLib/commit/2372efd3da1ccb226b4297222e25f41ecc84821d","https://github.com/nasa/CryptoLib/releases/tag/v1.4.3"],"weaknesses":["CWE-125"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/21xxx/CVE-2026-21900.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-21900","state":"PUBLISHED","datePublished":"2026-01-10T00:14:33.782Z","dateUpdated":"2026-01-13T17:16:34.273Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-01-05T17:24:36.931Z"},"containers":{"cna":{"title":"CryptoLib Has Out-of-Bounds Read in KMC Encrypt Metadata Parsing via Flawed strtok Pattern","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"nasa","product":"CryptoLib","versions":[{"version":"< 1.4.3","status":"affected"}]}],"references":[{"url":"https://github.com/nasa/CryptoLib/security/advisories/GHSA-4g6v-36fv-qcvw","name":"https://github.com/nasa/CryptoLib/security/advisories/GHSA-4g6v-36fv-qcvw","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/nasa/CryptoLib/commit/2372efd3da1ccb226b4297222e25f41ecc84821d","name":"https://github.com/nasa/CryptoLib/commit/2372efd3da1ccb226b4297222e25f41ecc84821d","tags":["x_refsource_MISC"]},{"url":"https://github.com/nasa/CryptoLib/releases/tag/v1.4.3","name":"https://github.com/nasa/CryptoLib/releases/tag/v1.4.3","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.2,"baseSeverity":"HIGH","vectorString":"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","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-125","lang":"en","description":"CWE-125: Out-of-bounds Read","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-01-10T00:14:33.782Z"},"source":{"advisory":"GHSA-4g6v-36fv-qcvw","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/nasa/CryptoLib/security/advisories/GHSA-4g6v-36fv-qcvw","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-01-13T17:16:31.457731Z","id":"CVE-2026-21900","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-01-13T17:16:34.273Z"}}]}}}