Libssh: incorrect return code handling in ssh_kdf() in libssh
Priority LOW 39CWE-682Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 16 fixed, 4 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.
Summary
A flaw was found in libssh versions built with OpenSSL versions older than 3.0, specifically in the ssh_kdf() function responsible for key derivation. Due to inconsistent interpretation of return values where OpenSSL uses 0 to indicate failure and libssh uses 0 for success—the function may mistakenly return a success status even when key derivation fails. This results in uninitialized cryptographic key buffers being used in subsequent communication, potentially compromising SSH sessions' confidentiality, integrity, and availability.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00513 43rd percentileScored 2026-11-07
Fix Partial libssh (libssh): 0.11.2Red Hat: 5 advisoriesRed Hat: 16 fixed, 4 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| libssh | libssh | before 0.11.2 | 0.11.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | 0.9.6-16.el8_10 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | 0.9.6-16.el8_10 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | — | 0.9.4-2.el8_4.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | — | 0.9.4-2.el8_4.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | — | 0.9.6-4.el8_6.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | — | 0.9.6-4.el8_6.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | — | 0.9.6-13.el8_8.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | — | 0.9.6-13.el8_8.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions | — | 0.9.6-3.el9_0.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 10 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | Not affected | CNA |
- libssh Vendorlibssh Affected before 0.11.2 Fixed in 0.11.2 Patch available CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in 0.9.6-16.el8_10 Patch available CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in 0.9.6-16.el8_10 Patch available CNA
- Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support VendorRed Hat Affected — Fixed in 0.9.4-2.el8_4.2 Patch available CNA
- Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On VendorRed Hat Affected — Fixed in 0.9.4-2.el8_4.2 Patch available CNA
- Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support VendorRed Hat Affected — Fixed in 0.9.6-4.el8_6.2 Patch available CNA
- Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On VendorRed Hat Affected — Fixed in 0.9.6-4.el8_6.2 Patch available CNA
- Red Hat Enterprise Linux 8.8 Telecommunications Update Service VendorRed Hat Affected — Fixed in 0.9.6-13.el8_8.2 Patch available CNA
- Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions VendorRed Hat Affected — Fixed in 0.9.6-13.el8_8.2 Patch available CNA
- Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions VendorRed Hat Affected — Fixed in 0.9.6-3.el9_0.2 Patch available CNA
- Red Hat Enterprise Linux 10 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — Not affected CNA
CPE configurations NVD · 7
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:* | before 0.11.2 | Vulnerable | libssh |
| cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:* | 4.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* | 6.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* | 8.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:* | 10.0 | Vulnerable | Red Hat |
- cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:* Versions before 0.11.2 Vulnerable ·libssh
- cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:* Versions 4.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Red Hat
Remediation
- Fix · CNA libssh (libssh) Fixed in 0.11.2
Red Hat 5 advisories
- RHSA-2026:25911 Released 2026-06-15 · Red Hat rating Moderatelibssh security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) libssh-devel-0.9.6-4.el8_6.2
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) libssh-devel-0.9.6-4.el8_6.2
- Red Hat Enterprise Linux BaseOS AUS (v.8.6) libssh-0.9.6-4.el8_6.2, libssh-config-0.9.6-4.el8_6.2
- Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) libssh-0.9.6-4.el8_6.2, libssh-config-0.9.6-4.el8_6.2
- RHSA-2026:24349 Released 2026-06-08 · Red Hat rating Moderatelibssh security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) libssh-devel-0.9.4-2.el8_4.2
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) libssh-devel-0.9.4-2.el8_4.2
- Red Hat Enterprise Linux BaseOS AUS (v.8.4) libssh-0.9.4-2.el8_4.2, libssh-config-0.9.4-2.el8_4.2
- Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) libssh-0.9.4-2.el8_4.2, libssh-config-0.9.4-2.el8_4.2
- RHSA-2026:20610 Released 2026-05-26 · Red Hat rating Moderatelibssh security update
- Red Hat Enterprise Linux AppStream E4S (v.8.8) libssh-devel-0.9.6-13.el8_8.2
- Red Hat Enterprise Linux AppStream TUS (v.8.8) libssh-devel-0.9.6-13.el8_8.2
- Red Hat Enterprise Linux BaseOS E4S (v.8.8) libssh-0.9.6-13.el8_8.2, libssh-config-0.9.6-13.el8_8.2
- Red Hat Enterprise Linux BaseOS TUS (v.8.8) libssh-0.9.6-13.el8_8.2, libssh-config-0.9.6-13.el8_8.2
Show 2 more Red Hat advisories
- RHSA-2025:23024 Released 2025-12-10 · Red Hat rating Moderatelibssh security update
- Red Hat Enterprise Linux AppStream E4S (v.9.0) libssh-devel-0.9.6-3.el9_0.2
- Red Hat Enterprise Linux BaseOS E4S (v.9.0) libssh-0.9.6-3.el9_0.2, libssh-config-0.9.6-3.el9_0.2
- RHSA-2025:21977 Released 2025-11-24 · Red Hat rating Moderatelibssh security update
- Red Hat Enterprise Linux AppStream (v. 8) libssh-devel-0.9.6-16.el8_10
- Red Hat Enterprise Linux BaseOS (v. 8) libssh-0.9.6-16.el8_10, libssh-config-0.9.6-16.el8_10
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
libssh 0.11.2
2 records Highest priority Priority LOW 2 LOW
Other records, highest priority first
- TI-2025-04805 Libssh: double free vulnerability in libssh key export functionsPriority LOW 30
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2025:21977 |
| Red Hat Enterprise Linux AppStream AUS (v.8.4) | Fixed | RHSA-2026:24349 |
| Red Hat Enterprise Linux AppStream AUS (v.8.6) | Fixed | RHSA-2026:25911 |
| Red Hat Enterprise Linux AppStream E4S (v.8.8) | Fixed | RHSA-2026:20610 |
| Red Hat Enterprise Linux AppStream E4S (v.9.0) | Fixed | RHSA-2025:23024 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) | Fixed | RHSA-2026:24349 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) | Fixed | RHSA-2026:25911 |
| Red Hat Enterprise Linux AppStream TUS (v.8.8) | Fixed | RHSA-2026:20610 |
| Red Hat Enterprise Linux BaseOS (v. 8) | Fixed | RHSA-2025:21977 |
| Red Hat Enterprise Linux BaseOS AUS (v.8.4) | Fixed | RHSA-2026:24349 |
| Red Hat Enterprise Linux BaseOS AUS (v.8.6) | Fixed | RHSA-2026:25911 |
| Red Hat Enterprise Linux BaseOS E4S (v.8.8) | Fixed | RHSA-2026:20610 |
| Red Hat Enterprise Linux BaseOS E4S (v.9.0) | Fixed | RHSA-2025:23024 |
| Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) | Fixed | RHSA-2026:24349 |
| Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) | Fixed | RHSA-2026:25911 |
| Red Hat Enterprise Linux BaseOS TUS (v.8.8) | Fixed | RHSA-2026:20610 |
Not affected: 2 products
- Red Hat Enterprise Linux 10
- Red Hat OpenShift Container Platform 4
Timeline
- 2026-10-02 Threatist record created from CVE-2025-5372
- 2026-10-03 Alias added: GHSA-59w5-j22f-h3rv
References
More Libssh vulnerabilities
- TI-2018-07745 Improper authentication in [UNKNOWN] libssh CVSS 3.0CRITICAL 9.1
- TI-2023-26623 The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6… CVSS 3.1MEDIUM 5.9
- TI-2012-03902 Multiple integer overflows in libssh before 0.5.3 allow remote attackers to cause a… CVSS 2.0HIGH 7.5
- TI-2019-11093 OS command injection in Red Hat libssh CVSS 3.1HIGH 8.8
- TI-2026-00732 Libssh: libssh: denial of service via zero-length input in ssh_get_hexa() CVSS 3.1HIGH 8.2
- TI-2012-03900 Multiple buffer overflows in libssh before 0.5.3 allow remote attackers to cause a denial… CVSS 2.0HIGH 7.5
Sources
- CVE-2025-5372 · CVE Program
- CVE-2025-5372 · NVD
- FIRST EPSS
- GHSA-59w5-j22f-h3rv · GitHub Advisory Database · CC BY 4.0
- CVE-2025-5372 · Red Hat security data · CC BY 4.0
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