{"id":"CVE-2026-21899","state":"PUBLISHED","title":"CryptoLib has an out-of-bounds read and crash vulnerability when decoding an empty Base64url string","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, in base64urlDecode, padding-stripping dereferences input[inputLen - 1] before checking that inputLen > 0 or that input != NULL. For inputLen == 0, this becomes an OOB read at input[-1], potentially crashing the process. If input == NULL and inputLen == 0, it dereferences NULL - 1. This issue has been patched in version 1.4.3.","publishedAt":"2026-01-10T00:11:18.877Z","updatedAt":"2026-01-12T20:23:08.304Z","severity":{"score":4.7,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L","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-wc29-5hw7-mpj8","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-2026-21899.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-21899","state":"PUBLISHED","datePublished":"2026-01-10T00:11:18.877Z","dateUpdated":"2026-01-12T20:23:08.304Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-01-05T17:24:36.931Z"},"containers":{"cna":{"title":"CryptoLib has an out-of-bounds read and crash vulnerability when decoding an empty Base64url string","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, in base64urlDecode, padding-stripping dereferences input[inputLen - 1] before checking that inputLen > 0 or that input != NULL. For inputLen == 0, this becomes an OOB read at input[-1], potentially crashing the process. If input == NULL and inputLen == 0, it dereferences NULL - 1. 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-wc29-5hw7-mpj8","name":"https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8","tags":["x_refsource_CONFIRM"]},{"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":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":4.7,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L","version":"3.1"}}],"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":"2026-01-10T00:11:18.877Z"},"source":{"advisory":"GHSA-wc29-5hw7-mpj8","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-01-12T20:22:54.955002Z","id":"CVE-2026-21899","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-01-12T20:23:08.304Z"}}]}}}