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.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 27 Jan 2026 16:15:00 +0000

Type Values Removed Values Added
Description 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.
Title Improper validation of PBMAC1 parameters in PKCS#12 MAC verification
Weaknesses CWE-476
CWE-787
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: openssl

Published:

Updated: 2026-01-27T15:59:41.681Z

Reserved: 2025-09-30T09:29:44.018Z

Link: CVE-2025-11187

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-01-27T16:16:14.093

Modified: 2026-01-27T16:16:14.093

Link: CVE-2025-11187

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses