CVE-2026-42770: FFC-DH Peer Validation Uses Attacker-Supplied q

CSIRTS triage

What: FFC-DH peer validation incorrectly uses attacker-supplied q values instead of validating them, weakening cryptographic assurance.
Who is affected: Systems using FFC-DH key exchange with OpenSSL for authentication or key establishment.
Urgency: Low priority; CVSS 3.7 indicates limited immediate risk, but authentication can be bypassed.
Action: Upgrade to an OpenSSL version that properly validates FFC-DH peer parameters.

AI-assisted analysis generated from the source advisory — verify against the original.

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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-2026-427700.47% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 38% of all EPSS-scored CVEs.

CVE	CSIRTS overview	External
CVE-2026-42770	coverage & exploitation status	NVD · CVE.org

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