{"id":"CVE-2026-21899","aliases":["EUVD-2026-1895","GHSA-wc29-5hw7-mpj8"],"status":"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 \u003e 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.","severity":{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00345,"percentile":0.28254,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-125"],"published":"2026-01-10T00:11:18Z","modified":"2026-10-28T02:30:34Z","products":[{"vendor":"nasa","product":"cryptolib"}],"references":[{"url":"https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8","tags":["x_refsource_CONFIRM","Exploit","Vendor Advisory","advisory"]},{"url":"https://github.com/nasa/CryptoLib/releases/tag/v1.4.3","tags":["x_refsource_MISC","Release Notes","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21899.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-21899","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-21899","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 \u003e 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.","status":"published","published":"2026-01-10T00:11:18.877Z","modified":"2026-01-12T20:23:08.304Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T13:41:42.05254Z"}],"euvd":[{"id":"EUVD-2026-1895","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 \u003e 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.","status":"published","published":"2026-01-10T00:11:18Z","modified":"2026-01-12T20:23:08Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L","level":"medium"}],"updated_at":"2026-11-02T19:48:53.22038Z"}],"nvd":[{"id":"CVE-2026-21899","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 \u003e 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.","status":"published","published":"2026-01-10T01:16:18.113Z","modified":"2026-06-17T10:19:06.903Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"secondary"},{"version":"3.1","score":4.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T14:12:03.683495Z"}],"osv":[{"id":"CVE-2026-21899","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 \u003e 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.","status":"published","published":"2026-01-10T00:11:18.877Z","modified":"2026-10-28T02:30:34.387507895Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L","level":"medium"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T15:44:58.42038Z"}]}}