[UPDATE] [high] libssh2: Multiple vulnerabilities

A remote, anonymous attacker can exploit multiple vulnerabilities in libssh2 to conduct a denial of service attack or execute code.

CSIRTS triage

What: Multiple vulnerabilities in libssh2 can lead to denial of service or code execution.
Who is affected: Deployments of libssh2 are affected.
Urgency: Remediation is high urgency due to the potential for exploitation and high severity.
Action: Apply patches as soon as they are available.

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.

Moderate exploitation riskCVE-2026-552002.0% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 79% of all EPSS-scored CVEs.
Low exploitation riskCVE-2026-551990.92% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 57% of all EPSS-scored CVEs.

CVE	CSIRTS overview	External
CVE-2026-55200	coverage & exploitation status	NVD · CVE.org
CVE-2026-55199	coverage & exploitation status	NVD · CVE.org

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.