CVE-2026-40253 - openCryptoki: Memory safety vulnerabilities in BER/DER decoders in asn1.c

CVE-2026-40253 - openCryptoki: Memory safety vulnerabilities in BER/DER decoders in asn1.c

https://cvefeed.io/rssfeed/latest.atom / Fri, 04/17/2026 - 07:01
CVE ID :CVE-2026-40253
Published : April 16, 2026, 11:16 p.m. | 4 hours, 54 minutes ago
Description :openCryptoki is a PKCS#11 library and provides tooling for Linux and AIX. In versions 3.26.0 and below, the BER/DER decoding functions in the shared common library (asn1.c) accept a raw pointer but no buffer length parameter, and trust attacker-controlled BER length fields without validating them against actual buffer boundaries. All primitive decoders are affected: ber_decode_INTEGER, ber_decode_SEQUENCE, ber_decode_OCTET_STRING, ber_decode_BIT_STRING, and ber_decode_CHOICE. Additionally, ber_decode_INTEGER can produce integer underflows when the encoded length is zero. An attacker supplying a malformed BER-encoded cryptographic object through PKCS#11 operations such as C_CreateObject or C_UnwrapKey, token loading from disk, or remote backend communication can trigger out-of-bounds reads. This affects all token backends (Soft, ICA, CCA, TPM, EP11, ICSF) since the vulnerable code is in the shared common library. A patch is available thorugh commit ed378f463ef73364c89feb0fc923f4dc867332a3.
Severity: 6.8 | MEDIUM
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