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🛡️ CVE-2026-0966 on Ubuntu — libssh

⚪ Unknown ✅ No Known Exploit OSV
N/A
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

A flaw was found in libssh. The API function ssh_get_hexa() is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to SSH_LOG_PACKET (3) or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process.

Distribution advisory

This page covers CVE-2026-0966 as tracked by Ubuntu, for the package libssh. The fix is available in version 0.11.2-1ubuntu0.2; earlier versions remain affected.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity low, availability high.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

  • Attack vector: Network — reachable from anywhere that can route to the service.
  • Attack complexity: Low — the attack works reliably, with no preparation.
  • Privileges required: None — an unauthenticated stranger can try it.
  • User interaction: None — nobody has to be tricked into anything.
  • Scope: Unchanged — the damage stays inside the vulnerable component.
  • Confidentiality impact: None.
  • Integrity impact: Low — limited, and the attacker does not choose what is affected.
  • Availability impact: High — total loss, or loss the attacker controls.

Weakness class

UBUNTU-CVE-2026-0966 is classified as CWE-124: Buffer Underwrite ('Buffer Underflow'). The product writes to a buffer using an index or pointer that references a memory location prior to the beginning of the buffer.

Affected software

UBUNTU-CVE-2026-0966 is recorded against 1 package.

  • libssh (fixed in 0.11.2-1ubuntu0.2)

Timeline and source

Published on 13 February 2026 and last revised on 14 May 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

ubuntu.com (Report)
www.cve.org (Report)
www.libssh.org (Report)
ubuntu.com (Advisory)
ubuntu.com (Advisory)

Other advisories for this package

libssh has other advisories on record. If you are patching this one, these are worth checking on the same host:

Same weakness in other software

These advisories are the same class of weakness (CWE-124: Buffer Underwrite ('Buffer Underflow')) in other software:

CVE-2026-0966 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity Unknown
CVSS Score N/A
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
CWE N/A
Public Exploit ✅ No
Source OSV
Published 2026-02-13
Updated 2026-08-20
Modified 2026-05-14
Fix URL N/A

Affected Packages

Software From version Fixed in
libssh — 0.11.2-1ubuntu0.2

Similar Threats

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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