libssh before 0.7.3 improperly truncates ephemeral secrets generated for the (1)…
Priority LOW 31CWE-200Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Fixed
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-200.
Summary
libssh before 0.7.3 improperly truncates ephemeral secrets generated for the (1) diffie-hellman-group1 and (2) diffie-hellman-group14 key exchange methods to 128 bits, which makes it easier for man-in-the-middle attackers to decrypt or intercept SSH sessions via unspecified vectors, aka a "bits/bytes confusion bug."
Why it matters now
EPSS 0.02431 84th percentileScored 2026-11-07
Fix Fixed Red Hat: 1 advisory
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 9
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Red Hat |
| cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:* | 12.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* | 14.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:* | 15.10 | Vulnerable | Canonical |
| cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:* | up to 0.7.2 | Vulnerable | libssh |
| cpe:2.3:o:fedoraproject:fedora:22:*:*:*:*:*:*:* | 22 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:23:*:*:*:*:*:*:* | 23 | Vulnerable | Fedoraproject |
| cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Debian |
| cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* | 8.0 | Vulnerable | Debian |
- cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
- cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:* Versions 12.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* Versions 14.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:* Versions 15.10 Vulnerable ·Canonical
- cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:* Versions up to 0.7.2 Vulnerable ·libssh
- cpe:2.3:o:fedoraproject:fedora:22:*:*:*:*:*:*:* Versions 22 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:23:*:*:*:*:*:*:* Versions 23 Vulnerable ·Fedoraproject
- cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Debian
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Debian
Remediation
Red Hat 1 advisory
- RHSA-2016:0566 Released 2016-03-31 · Red Hat rating Moderatelibssh security update
- Red Hat Enterprise Linux 7 Extras libssh-0.7.1-2.el7, libssh-devel-0.7.1-2.el7
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 7 Extras | Fixed | RHSA-2016:0566 |
Timeline
- 2026-10-02 Threatist record created from CVE-2016-0739
- 2026-10-03 Alias added: GHSA-v7q8-7g48-2272
References
Advisory 9
Sources
- CVE-2016-0739 · CVE Program
- CVE-2016-0739 · NVD
- FIRST EPSS
- GHSA-v7q8-7g48-2272 · GitHub Advisory Database · CC BY 4.0
- CVE-2016-0739 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences