CVE-2026-34181: PKCS#12 Files with PBMAC1 Are Accepted with Short HMAC Keys
CSIRTS triage
- What
- PKCS#12 files with PBMAC1 are accepted with short HMAC keys, which is a security risk.
- Who is affected
- Users of PKCS#12 files are affected by this vulnerability.
- Urgency
- High urgency for remediation due to the potential for exploitation with high severity.
- Action
- Implement a patch or workaround to ensure HMAC keys are of sufficient length.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-34181
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-341810.20% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 9% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-34181 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- high[UPDATE] [high] OpenSSL: Multiple Vulnerabilitiescert-bund
- unknownMultiple vulnerabilities in Tenable Identity Exposure (June 24, 2026)cert-fr-avis
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