USN-8093-2: libssh vulnerability

unknownCVE-2026-3731

USN-8093-1 fixed a vulnerability in libssh. This update provides the corresponsing fix for Ubuntu 26.04 LTS. Original advisory details: It was discovered that libssh incorrectly performed bounds checking when processing SFTP extensions. If a client application queried extension data out of bounds, it could cause the application to crash, resulting in a denial of service, or exhibit unintended behavior.

CSIRTS triage

vendor: libssh product: libssh Denial of service Information disclosure

What: Incorrect bounds checking when processing SFTP extensions allows out-of-bounds queries to cause application crashes or unintended behavior.
Who is affected: Client applications using libssh for SFTP connections.
Urgency: Low-to-Medium priority; denial of service and potential information disclosure via crash behavior requires patching.
Action: Update libssh to the patched version addressing CVE-2026-3731.

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

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Details

Source: Ubuntu Security Notices (INTL · vendor-psirt · site)
Severity: unknown
Published: 2026-08-19
Exploitation: Not in CISA KEV at last sync

Original advisory: https://ubuntu.com/security/notices/USN-8093-2

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-2026-37310.63% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 47% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-3731	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

medium[UPDATE] [medium] libssh: Vulnerability allows Denial of Servicecert-bund
unknownDSA-6410-1 libssh - security updatedebian
high[UPDATE] [high] IBM App Connect Enterprise: Multiple vulnerabilitiescert-bund