CVE-2026-55199
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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Exploitation outlook
- Low exploitation risk0.92% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 58% of all EPSS-scored CVEs.
Advisory coverage (5)
- high[UPDATE] [high] libssh2: Multiple vulnerabilitiescert-bund · 2026-08-25
- unknownMultiple vulnerabilities in Microsoft Azure Linux (July 7, 2026)cert-fr-avis · 2026-07-07
- unknownDSA-6365-1 libssh2 - security updatedebian · 2026-06-25
- unknownNCSC-2026-0210 [1.01] [M/H] Vulnerabilities fixed in libssh2 by libsshncsc-nl · 2026-06-24
- mediumCVE-2026-55199: libssh2 - Pre-Authentication DoS via SSH_MSG_EXT_INFO Handlermsrc · 2026-06-09
External references
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