Distribution advisory
This page covers CVE-2025-61985 as tracked by Ubuntu, for the package openssh. The fix is available in version 1:10.2p1-2ubuntu1; earlier versions remain affected.
How this vulnerability can be exploited
This issue can be reached with local access to the system, attack complexity is high, an attacker needs low-level privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality low, integrity low, availability none.
CVSS metrics in full
The score comes from this vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
- Attack vector: Local — a local account, shell or session on the host is needed.
- Attack complexity: High — the attacker first has to win a race, learn a secret or otherwise prepare the target.
- Privileges required: Low — an ordinary user account is enough.
- User interaction: None — nobody has to be tricked into anything.
- Scope: Unchanged — the damage stays inside the vulnerable component.
- Confidentiality impact: Low — limited, and the attacker does not choose what is affected.
- Integrity impact: Low — limited, and the attacker does not choose what is affected.
- Availability impact: None.
Weakness class
UBUNTU-CVE-2025-61985 is classified as CWE-158: Improper Neutralization of Null Byte or NUL Character. The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes NUL characters or null bytes when they are sent to a downstream component.
Affected software
UBUNTU-CVE-2025-61985 is recorded against 2 packages.
- openssh (fixed in 1:10.2p1-2ubuntu1)
- openssh-ssh1
Timeline and source
Published on 6 October 2025 and last revised on 20 May 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.
References
ubuntu.com (Report)
www.cve.org (Report)
www.openwall.com (Report)
marc.info (Report)
www.openssh.com (Report)
ubuntu.com (Advisory)
ubuntu.com (Advisory)
Other advisories for this package
openssh 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-158: Improper Neutralization of Null Byte or NUL Character) in other software:
