CVE-2026-21899: medium-severity vulnerability in nasa CryptoLib
CryptoLib has an out-of-bounds read and crash vulnerability when decoding an empty Base64url string
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 4.7epss 0.3%
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.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L
Affected products
nasa · CryptoLibRelated CVEs — nasa CryptoLib
In the same product, most dangerous first.
CVE-2025-30216CRITICALCryptoLib Has Heap Overflow in Crypto_TM_ProcessSecurity due to Unchecked Secondary Header LengthEPSS 2.6%CVE-2025-29912HIGHCryptoLib Has Heap Buffer Overflow Due to Unsigned Integer Underflow in Crypto_TC_ProcessSecurityEPSS 1.1%CVE-2025-29909HIGHCryptoLib's Crypto_TC_ApplySecurity() Has a Heap Buffer Overflow VulnerabilityEPSS 1.1%CVE-2025-59534HIGHCryptoLib command Injection vulnerability in initialize_kerberos_keytab_file_login()EPSS 0.9%CVE-2025-29911HIGHCryptoLib Has Heap Buffer Overflow in Crypto_AOS_ProcessSecurity FunctionEPSS 0.7%CVE-2025-29913HIGHCryptoLib's Crypto_TC_Prep_AAD Has Buffer Overflow Due to Integer UnderflowEPSS 0.7%