PKCS#12 Files with PBMAC1 Are Accepted with Short HMAC Keys
Summary
| CVE | CVE-2026-34181 |
|---|---|
| State | PUBLISHED |
| Assigner | openssl |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-06-09 17:17:04 UTC |
| Updated | 2026-06-15 18:13:13 UTC |
| Description | Issue Summary: The PKCS#12 file processing fails to perform sufficient input validation for files that use Password-Based Message Authentication Code 1 (PBMAC1) integrity mechanism allowing a certificate and private key forgery. Impact Summary: An attacker impersonating a user can cause a service reading PKCS#12 files to accept forged certificates and private keys with a 1 in 256 probability. If a service accepting PKCS#12 files is using passwords for authenticating the received files, the attacker can create unencrypted PKCS#12 files that use PBMAC1 authentication that specifies an HMAC key of only one byte, allowing them to craft a file that will be accepted with a 1 in 256 probability. That would then cause the service to accept a certificate and private key controlled by the attacker. The FIPS modules are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary. |
Risk And Classification
Primary CVSS: v3.1 7.4 HIGH from ADP
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS: 0.001940000 probability, percentile 0.092030000 (date 2026-06-16)
Problem Types: CWE-354 | CWE-354 CWE-354 Improper Validation of Integrity Check Value
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 7.4 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 7.4 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD Known Affected Configurations (CPE 2.3)
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/openssl/openssl/commit/0300eb9ddce7a0895bf301a4b0c03a9da2313a0f | [email protected] | github.com | Patch |
| github.com/openssl/openssl/commit/ec36f2417c4ddd8cabce4b4a60a3d7a7365f2d81 | [email protected] | github.com | Patch |
| github.com/openssl/openssl/commit/79eb76a937e474bb7610a0a3dc57131dc8dc6610 | [email protected] | github.com | Patch |
| github.com/openssl/openssl/commit/85dcbb3abaa4878af5c8fbbe11bce708fcf984a7 | [email protected] | github.com | Patch |
| openssl-library.org/news/secadv/20260609.txt | [email protected] | openssl-library.org | Vendor Advisory |
| github.com/openssl/security/commit/0300eb9ddce7a0895bf301a4b0c03a9da2313a0f | MITRE | github.com | |
| github.com/openssl/security/commit/79eb76a937e474bb7610a0a3dc57131dc8dc6610 | MITRE | github.com | |
| github.com/openssl/security/commit/85dcbb3abaa4878af5c8fbbe11bce708fcf984a7 | MITRE | github.com | |
| github.com/openssl/security/commit/ec36f2417c4ddd8cabce4b4a60a3d7a7365f2d81 | MITRE | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Pavol Žáčik (Red Hat) (en)
CNA: Alex Gaynor (Anthropic) (en)
CNA: Alicja Kario (Red Hat) (en)
There are currently no legacy QID mappings associated with this CVE.