CVE-2026-59846: libssh OS Command Injection
CVSS: 3.9v3.1LowModified
AliasesUBUNTU-CVE-2026-59846DEBIAN-CVE-2026-59846CGA-7j44-mggj-qxvmCGA-h66h-f49m-6w24CGA-mhq3-3c9m-hfhqCGA-q7jw-x9qv-wxhhCGA-r895-382c-x8mxCGA-vp87-gjqp-23m8
Published 21-07-2026Last modified 01-09-2026
Vulnerability summary
CVE-2026-59846 is a low (CVSS 3.9) OS Command Injection vulnerability in libssh. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 1.6% of scored vulnerabilities.
CVSS score
3.9/10
010
Low · v3.1 (CVE.org)EPSS score
0.12%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 16 · Related 12MGASA-2026-0425OPENSUSE-SU-2026:11377-1OPENSUSE-SU-2026:21444-1RHSA-2026:42922RHSA-2026:55855RHSA-2026:62217RHSA-2026:62218SUSE-SU-2026:22940-1SUSE-SU-2026:22948-1SUSE-SU-2026:22956-1SUSE-SU-2026:23056-1SUSE-SU-2026:23168-1SUSE-SU-2026:3302-1SUSE-SU-2026:3330-1SUSE-SU-2026:3463-1USN-8699-1CGA-7V43-4X49-5HC4
Timeline
- 21-07-2026PublishedVulnerability first disclosed.
- 01-09-2026Last modifiedVulnerability information updated.
Description
A flaw was found in libssh. A malicious username expanded through %r in ProxyCommand handling can inject shell metacharacters, exposing environment variables and causing unintended shell behavior.
CVSS metrics
4 scores · 4 sources · 1 versionLow 3.9Preferred score · CVE.org (CNA)
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:NSourcesAll 4 agree
- OSV · UbuntuEcosystem advisory · calculated3.9LowCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
- OSV · DebianEcosystem advisory · calculated3.9LowCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
- NVDNIST3.9LowCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
EPSS trend
Probability
0.12%
Chance of exploitation in the next 30 days
Percentile
2%
Versus all other CVEs
30-day change
0.00 pp
From 0.12% on 18-09-2026
18-09-202618-10-2026
EPSS score0.12%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.
- CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.
Affected systems
Chainguard3 products
- libssh< 0.12.1-r0
- libssh-dev< 0.12.1-r0
- libssh2All versions (No fix recorded)
Wolfi3 products
- libssh< 0.12.1-r0
- libssh-dev< 0.12.1-r0
- libssh2All versions (No fix recorded)
Redhat2 products
- enterprise_linux8.0 | 9.0 | 10.0
- hardened_imagesna
Debian1 product
- libsshAll versions (No fix recorded) | < 0.11.5-0+deb13u1 | < 0.12.1-1
Libssh1 product
- libsshna
Ubuntu1 product
- libsshAll versions (No fix recorded) | < 0.9.6-2ubuntu0.22.04.8 | < 0.10.6-2ubuntu0.5 | < 0.11.3-1ubuntu2.1
6 vendors · 11 products
