🔐 CVE Alert

CVE-2025-11187

MEDIUM 6.1

Improper validation of PBMAC1 parameters in PKCS#12 MAC verification

CVSS Score
6.1
EPSS Score
0.0%
EPSS Percentile
2th

Issue summary: PBMAC1 parameters in PKCS#12 files are missing validation which can trigger a stack-based buffer overflow, invalid pointer or NULL pointer dereference during MAC verification. Impact summary: The stack buffer overflow or NULL pointer dereference may cause a crash leading to Denial of Service for an application that parses untrusted PKCS#12 files. The buffer overflow may also potentially enable code execution depending on platform mitigations. When verifying a PKCS#12 file that uses PBMAC1 for the MAC, the PBKDF2 salt and keylength parameters from the file are used without validation. If the value of keylength exceeds the size of the fixed stack buffer used for the derived key (64 bytes), the key derivation will overflow the buffer. The overflow length is attacker-controlled. Also, if the salt parameter is not an OCTET STRING type this can lead to invalid or NULL pointer dereference. Exploiting this issue requires a user or application to process a maliciously crafted PKCS#12 file. It is uncommon to accept untrusted PKCS#12 files in applications as they are usually used to store private keys which are trusted by definition. For this reason the issue was assessed as Moderate severity. The FIPS modules in 3.6, 3.5 and 3.4 are not affected by this issue, as PKCS#12 processing is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5 and 3.4 are vulnerable to this issue. OpenSSL 3.3, 3.0, 1.1.1 and 1.0.2 are not affected by this issue as they do not support PBMAC1 in PKCS#12.

CWE CWE-787 CWE-476
Vendor openssl
Product openssl
Ecosystems
Industries
TechnologySecurity
Published Jan 27, 2026
Last Updated Mar 20, 2026
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Affected Versions

OpenSSL / OpenSSL
3.6.0 < 3.6.1 3.5.0 < 3.5.5 3.4.0 < 3.4.4

References

NVD ↗ CVE.org ↗ EPSS Data ↗
openssl-library.org: https://openssl-library.org/news/secadv/20260127.txt github.com: https://github.com/openssl/openssl/commit/8caf359d6e46fb413e8f5f0df765d2e8a51df4e8 github.com: https://github.com/openssl/openssl/commit/e1079bc17ed93ff16f6b86f33a2fe3336e78817e github.com: https://github.com/openssl/openssl/commit/205e3a55e16e4bd08c12fdbd3416ab829c0f6206 github.com: https://github.com/metadust/CVE-2025-11187

Credits

🔍 Stanislav Fort (Aisle Research) 🔍 Petr Šimeček (Aisle Research) 🔍 Hamza (Metadust) Tomáš Mráz