{"schemaVersion":3,"id":"CVE-2026-21899","aliases":[],"status":"published","duplicateOf":null,"title":null,"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.","dates":{"published":"2026-01-10T00:11:18.877Z","modified":"2026-01-12T20:23:08.304Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":4.9,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":4.7,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":4.9,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00345,"percentile":0.26542,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":-0.005000000000000013,"baselineDate":"2026-09-20T00:00:00.000Z","baselineScore":0.0035},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00345,"percentile":0.26542}],"last30":[{"date":"2026-09-20T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.0035,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00345,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00345,"percentile":0.26542}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[{"id":"GITHUB_NASA_CRYPTOLIB","name":"Cryptolib","source":"github","url":"https://github.com/nasa/CryptoLib/security/advisories/GHSA-q2pc-c3jx-3852","maturity":"poc","reliabilityScore":0.3,"verified":false,"type":null,"platforms":[],"requiresAuth":null,"exploitdb":null,"metasploit":null}],"exploitCount":1,"weaknesses":[{"id":"CWE-125","name":"Out-of-bounds Read","description":"The product reads data past the end, or before the beginning, of the intended buffer.","type":"weakness","status":"Draft","abstraction":"Base","likelihoodOfExploit":null,"url":"https://cwe.mitre.org/data/definitions/125.html"}],"affected":[{"vendor":"nasa","product":"cryptolib","name":"cryptolib","label":"cryptolib","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 1.4.3","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 1.4.3","eol":null,"hubHref":"/vendor/nasa/cryptolib"}],"affectedCount":1,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8","label":"github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8","hostname":"github.com","tags":["X Refsource CONFIRM","Exploit","Vendor Advisory"]},{"url":"https://github.com/nasa/CryptoLib/releases/tag/v1.4.3","label":"github.com/nasa/CryptoLib/releases/tag/v1.4.3","hostname":"github.com","tags":["X Refsource MISC","Release Notes"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-01-10T00:11:18.877Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-01-12T20:23:08.304Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":30,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-21T07:41:41.751Z","stale":false,"partial":false}}