CVE-2026-9547
CVE-2026-9547 · SSH improper host validation
This page contains facts from public vulnerability sources. Check the original advisory before updating.
When a libcurl-based application performs transfers via `SCP://` or `SFTP://` and utilizes the `CURLOPT_SSH_KEYFUNCTION` callback, it may silently accept an untrusted server. This vulnerability occurs when a server presents a host key type that does not match the specific key type already recorded for that host in the `known_hosts` file. Instead of rejecting the mismatch, the callback mechanism fails to properly enforce the restriction, allowing the connection to succeed without warning and risking a potential man-in-the-middle attack.
CVSS 7.4 · High · EPSS 0.3% · Fix available
- Published
- Updated
Stack: system
Affected products and versions
curl
- Versions
- ≥ 7.69.0, < 8.14.2: Affected (semver)
- ≥ 8.15.0, < 8.16.1: Affected (semver)
- ≥ 8.17.0, < 8.20.1: Affected (semver)
Update to 8.14.2; Update to 8.16.1; Update to 8.20.1
curl
- Versions
- ≥ 507cf6a13db0375eadd4655b4c64710db29e9cf2, < 0b8dbbc63c98777e4584cb9fbd71df3464008ad1: Affected (git)
No fix published
curl
- Versions
- 8.20.0: Affected
- 8.19.0: Affected
- 8.18.0: Affected
- 8.17.0: Affected
- 8.16.0: Affected
- 8.15.0: Affected
- 8.14.1: Affected
- 8.14.0: Affected
- 8.13.0: Affected
- 8.12.1: Affected
- 8.12.0: Affected
- 8.11.1: Affected
- 8.11.0: Affected
- 8.10.1: Affected
- 8.10.0: Affected
- 8.9.1: Affected
- 8.9.0: Affected
- 8.8.0: Affected
- 8.7.1: Affected
- 8.7.0: Affected
- 8.6.0: Affected
- 8.5.0: Affected
- 8.4.0: Affected
- 8.3.0: Affected
- 8.2.1: Affected
- 8.2.0: Affected
- 8.1.2: Affected
- 8.1.1: Affected
- 8.1.0: Affected
- 8.0.1: Affected
- 8.0.0: Affected
- 7.88.1: Affected
- 7.88.0: Affected
- 7.87.0: Affected
- 7.86.0: Affected
- 7.85.0: Affected
- 7.84.0: Affected
- 7.83.1: Affected
- 7.83.0: Affected
- 7.82.0: Affected
- 7.81.0: Affected
- 7.80.0: Affected
- 7.79.1: Affected
- 7.79.0: Affected
- 7.78.0: Affected
- 7.77.0: Affected
- 7.76.1: Affected
- 7.76.0: Affected
- 7.75.0: Affected
- 7.74.0: Affected
- 7.73.0: Affected
- 7.72.0: Affected
- 7.71.1: Affected
- 7.71.0: Affected
- 7.70.0: Affected
- 7.69.1: Affected
- 7.69.0: Affected
No fix published
curl Debian:12
- Versions
- 7.88.1-10
- 7.88.1-10+deb12u1
- 7.88.1-10+deb12u11
- 7.88.1-10+deb12u12
- 7.88.1-10+deb12u13
- 7.88.1-10+deb12u14
- 7.88.1-10+deb12u15
- 7.88.1-10+deb12u1~bpo11+1
- 7.88.1-10+deb12u2
- 7.88.1-10+deb12u3
- 7.88.1-10+deb12u3~bpo11+1
- 7.88.1-10+deb12u4
- 7.88.1-10+deb12u5
- 7.88.1-10+deb12u5~bpo11+1
- 7.88.1-10+deb12u6
- 7.88.1-10+deb12u6~bpo11+1
- 7.88.1-10+deb12u7
- 7.88.1-10+deb12u8
- 7.88.1-10+deb12u9
- 7.88.1-11
- 8.0.1-1~exp1
- 8.10.0-1
- 8.10.0-2
- 8.10.1-1
- 8.10.1-1~bpo12+1
- 8.10.1-2
- 8.11.0-1
- 8.11.1-1
- 8.11.1-1~bpo12+1
- 8.12.0+git20250209.89ed161+ds-1
- 8.12.0+git20250209.89ed161+ds-1~bpo12+1
- 8.12.1-1
- 8.12.1-2
- 8.12.1-2~bpo12+1
- 8.12.1-3
- 8.12.1-3~bpo12+1
- 8.13.0-1
- 8.13.0-1+exp1
- 8.13.0-2
- 8.13.0-2+exp1
- 8.13.0-3
- 8.13.0-4
- 8.13.0-4+exp1
- 8.13.0-5
- 8.13.0-5+exp1
- 8.13.0-5~bpo12+1
- 8.13.0~rc-1~exp1
- 8.13.0~rc-1~exp2
- 8.13.0~rc2-1
- 8.13.0~rc2-2
- 8.13.0~rc3-1
- 8.13.0~rc3-1+exp1
- 8.14.0-1
- 8.14.0-1+exp1
- 8.14.0~rc1-1+exp1
- 8.14.0~rc2-1+exp1
- 8.14.0~rc3-1+exp1
- 8.14.1-1
- 8.14.1-1~bpo12+1
- 8.14.1-2
- 8.14.1-2+exp1
- 8.14.1-2~bpo12+1
- 8.15.0-1
- 8.15.0-1~bpo13+1
- 8.15.0-1~exp1
- 8.15.0~rc1-1exp1
- 8.15.0~rc2-1~exp1
- 8.15.0~rc3-1~exp1
- 8.16.0-1
- 8.16.0-1+exp1
- 8.16.0-1~bpo13+1
- 8.16.0-2
- 8.16.0-3
- 8.16.0-4
- 8.16.0-4~bpo13+1
- 8.16.0~rc1-1~exp1
- 8.16.0~rc2-1
- 8.16.0~rc2-2
- 8.16.0~rc3-1
- 8.17.0-1
- 8.17.0-2
- 8.17.0-3
- 8.17.0~rc1-1~exp1
- 8.17.0~rc2-1
- 8.17.0~rc3-1
- 8.18.0-1
- 8.18.0-1~bpo13+1
- 8.18.0-2
- 8.18.0~rc1-1+exp1
- 8.18.0~rc2-1
- 8.18.0~rc3-1
- 8.19.0-1
- 8.19.0-1+exp1
- 8.19.0-1~bpo13+1
- 8.19.0-2
- 8.19.0-3
- 8.19.0-3+exp1
- 8.19.0-3+exp2
- 8.19.0~rc1-1~exp1
- 8.19.0~rc2-1
- 8.19.0~rc2-2
- 8.19.0~rc3-1
- 8.2.1-1
- 8.2.1-2
- 8.2.1-2~bpo12+1
- 8.20.0-1
- 8.20.0-1+exp
- 8.20.0-2
- 8.20.0-2+exp1
- 8.20.0-2~bpo13+1
- 8.20.0-3
- 8.20.0-4
- 8.20.0-5
- 8.20.0-5~bpo13+1
- 8.20.0~rc1-1+exp1
- 8.20.0~rc1-1+exp2
- 8.20.0~rc1-1+exp3
- 8.20.0~rc2-1
- 8.20.0~rc2-1+exp1
- 8.20.0~rc3-1
- 8.20.0~rc3-1+exp1
- 8.21.0-1
- 8.21.0-1+exp1
- 8.21.0-2
- 8.21.0-2+exp1
- 8.21.0-2~bpo13+1
- 8.21.0~rc1-1+exp1
- 8.21.0~rc2-1
- 8.21.0~rc2-1+exp1
- 8.21.0~rc3-1
- 8.21.0~rc3-1+exp1
- 8.22.0-1
- 8.22.0-1+exp1
- 8.22.0~rc2-1
- 8.22.0~rc2-2
- 8.22.0~rc3-1
- 8.22.0~rc3-1+exp1
- 8.23.0~rc1-1
- 8.23.0~rc1-2
- 8.23.0~rc2-1
- 8.23.0~rc2-1+exp1
- 8.3.0-1
- 8.3.0-2
- 8.3.0-2~bpo12+1
- 8.3.0-2~exp1
- 8.3.0-3
- 8.4.0-1
- 8.4.0-2
- 8.4.0-2~bpo12+1
- 8.5.0-1
- 8.5.0-1+exp1
- 8.5.0-2
- 8.5.0-2+exp1
- 8.5.0-2~bpo12+1
- 8.6.0-1
- 8.6.0-1.1
- 8.6.0-2
- 8.6.0-3
- 8.6.0-3.1
- 8.6.0-3.1~exp1
- 8.6.0-3.1~exp2
- 8.6.0-3.2
- 8.6.0-4
- 8.7.1-1
- 8.7.1-1+exp1
- 8.7.1-2
- 8.7.1-3
- 8.7.1-4
- 8.7.1-5
- 8.7.1-5+exp1
- 8.7.1-5~bpo12+1
- 8.8.0-1
- 8.8.0-1+exp1
- 8.8.0-1+exp2
- 8.8.0-1~bpo12+1
- 8.8.0-2
- 8.8.0-3
- 8.8.0-4
- 8.9.0-1
- 8.9.0-2
- 8.9.0-3
- 8.9.1-1
- 8.9.1-2
- 8.9.1-2~bpo12+1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
curl Debian:13
- Versions
- 8.14.1-2
- 8.14.1-2+deb13u1
- 8.14.1-2+deb13u2
- 8.14.1-2+deb13u2~bpo13+1
- 8.14.1-2+deb13u3
- 8.14.1-2+deb13u4
- 8.14.1-2+deb13u5
- 8.14.1-2+exp1
- 8.15.0-1
- 8.15.0-1~bpo13+1
- 8.15.0-1~exp1
- 8.15.0~rc1-1exp1
- 8.15.0~rc2-1~exp1
- 8.15.0~rc3-1~exp1
- 8.16.0-1
- 8.16.0-1+exp1
- 8.16.0-1~bpo13+1
- 8.16.0-2
- 8.16.0-3
- 8.16.0-4
- 8.16.0-4~bpo13+1
- 8.16.0~rc1-1~exp1
- 8.16.0~rc2-1
- 8.16.0~rc2-2
- 8.16.0~rc3-1
- 8.17.0-1
- 8.17.0-2
- 8.17.0-3
- 8.17.0~rc1-1~exp1
- 8.17.0~rc2-1
- 8.17.0~rc3-1
- 8.18.0-1
- 8.18.0-1~bpo13+1
- 8.18.0-2
- 8.18.0~rc1-1+exp1
- 8.18.0~rc2-1
- 8.18.0~rc3-1
- 8.19.0-1
- 8.19.0-1+exp1
- 8.19.0-1~bpo13+1
- 8.19.0-2
- 8.19.0-3
- 8.19.0-3+exp1
- 8.19.0-3+exp2
- 8.19.0~rc1-1~exp1
- 8.19.0~rc2-1
- 8.19.0~rc2-2
- 8.19.0~rc3-1
- 8.20.0-1
- 8.20.0-1+exp
- 8.20.0-2
- 8.20.0-2+exp1
- 8.20.0-2~bpo13+1
- 8.20.0-3
- 8.20.0-4
- 8.20.0-5
- 8.20.0-5~bpo13+1
- 8.20.0~rc1-1+exp1
- 8.20.0~rc1-1+exp2
- 8.20.0~rc1-1+exp3
- 8.20.0~rc2-1
- 8.20.0~rc2-1+exp1
- 8.20.0~rc3-1
- 8.20.0~rc3-1+exp1
- 8.21.0-1
- 8.21.0-1+exp1
- 8.21.0-2
- 8.21.0-2+exp1
- 8.21.0-2~bpo13+1
- 8.21.0~rc1-1+exp1
- 8.21.0~rc2-1
- 8.21.0~rc2-1+exp1
- 8.21.0~rc3-1
- 8.21.0~rc3-1+exp1
- 8.22.0-1
- 8.22.0-1+exp1
- 8.22.0~rc2-1
- 8.22.0~rc2-2
- 8.22.0~rc3-1
- 8.22.0~rc3-1+exp1
- 8.23.0~rc1-1
- 8.23.0~rc1-2
- 8.23.0~rc2-1
- 8.23.0~rc2-1+exp1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
curl Debian:14
- Versions
- 8.14.1-2
- 8.14.1-2+exp1
- 8.15.0-1
- 8.15.0-1~bpo13+1
- 8.15.0-1~exp1
- 8.15.0~rc1-1exp1
- 8.15.0~rc2-1~exp1
- 8.15.0~rc3-1~exp1
- 8.16.0-1
- 8.16.0-1+exp1
- 8.16.0-1~bpo13+1
- 8.16.0-2
- 8.16.0-3
- 8.16.0-4
- 8.16.0-4~bpo13+1
- 8.16.0~rc1-1~exp1
- 8.16.0~rc2-1
- 8.16.0~rc2-2
- 8.16.0~rc3-1
- 8.17.0-1
- 8.17.0-2
- 8.17.0-3
- 8.17.0~rc1-1~exp1
- 8.17.0~rc2-1
- 8.17.0~rc3-1
- 8.18.0-1
- 8.18.0-1~bpo13+1
- 8.18.0-2
- 8.18.0~rc1-1+exp1
- 8.18.0~rc2-1
- 8.18.0~rc3-1
- 8.19.0-1
- 8.19.0-1+exp1
- 8.19.0-1~bpo13+1
- 8.19.0-2
- 8.19.0-3
- 8.19.0-3+exp1
- 8.19.0-3+exp2
- 8.19.0~rc1-1~exp1
- 8.19.0~rc2-1
- 8.19.0~rc2-2
- 8.19.0~rc3-1
- 8.20.0-1
- 8.20.0-1+exp
- 8.20.0-2
- 8.20.0-2+exp1
- 8.20.0-2~bpo13+1
- 8.20.0-3
- 8.20.0-4
- 8.20.0-5
- 8.20.0-5~bpo13+1
- 8.20.0~rc1-1+exp1
- 8.20.0~rc1-1+exp2
- 8.20.0~rc1-1+exp3
- 8.20.0~rc2-1
- 8.20.0~rc2-1+exp1
- 8.20.0~rc3-1
- 8.20.0~rc3-1+exp1
- 8.21.0~rc1-1+exp1
- Affected ranges
- ECOSYSTEM: < 8.21.0~rc2-1
Update to 8.21.0~rc2-1
curl Ubuntu:22.04:LTS
- Versions
- 7.74.0-1.3ubuntu2
- 7.74.0-1.3ubuntu3
- 7.80.0-3
- 7.81.0-1
- 7.81.0-1ubuntu1.1
- 7.81.0-1ubuntu1.2
- 7.81.0-1ubuntu1.3
- 7.81.0-1ubuntu1.4
- 7.81.0-1ubuntu1.6
- 7.81.0-1ubuntu1.7
- 7.81.0-1ubuntu1.8
- 7.81.0-1ubuntu1.10
- 7.81.0-1ubuntu1.11
- 7.81.0-1ubuntu1.13
- 7.81.0-1ubuntu1.14
- 7.81.0-1ubuntu1.15
- 7.81.0-1ubuntu1.16
- 7.81.0-1ubuntu1.17
- 7.81.0-1ubuntu1.18
- 7.81.0-1ubuntu1.19
- 7.81.0-1ubuntu1.20
- 7.81.0-1ubuntu1.21
- 7.81.0-1ubuntu1.22
- 7.81.0-1ubuntu1.23
- 7.81.0-1ubuntu1.24
- Affected ranges
- ECOSYSTEM: < 7.81.0-1ubuntu1.25
Update to 7.81.0-1ubuntu1.25
curl Ubuntu:24.04:LTS
- Versions
- 8.2.1-1ubuntu3
- 8.2.1-1ubuntu3.1
- 8.4.0-2ubuntu1
- 8.5.0-2ubuntu1
- 8.5.0-2ubuntu2
- 8.5.0-2ubuntu8
- 8.5.0-2ubuntu9
- 8.5.0-2ubuntu10
- 8.5.0-2ubuntu10.1
- 8.5.0-2ubuntu10.2
- 8.5.0-2ubuntu10.3
- 8.5.0-2ubuntu10.4
- 8.5.0-2ubuntu10.5
- 8.5.0-2ubuntu10.6
- 8.5.0-2ubuntu10.7
- 8.5.0-2ubuntu10.8
- 8.5.0-2ubuntu10.9
- Affected ranges
- ECOSYSTEM: < 8.5.0-2ubuntu10.10
Update to 8.5.0-2ubuntu10.10
curl Ubuntu:25.10
- Versions
- 8.12.1-3ubuntu1
- 8.13.0-5ubuntu1
- 8.14.1-1ubuntu2
- 8.14.1-1ubuntu3
- 8.14.1-2ubuntu1
- 8.14.1-2ubuntu1.1
- 8.14.1-2ubuntu1.2
- 8.14.1-2ubuntu1.3
- Affected ranges
- ECOSYSTEM: < 8.14.1-2ubuntu1.4
Update to 8.14.1-2ubuntu1.4
curl Ubuntu:26.04:LTS
- Versions
- 8.14.1-2ubuntu1
- 8.17.0-1ubuntu1
- 8.18.0-1ubuntu1
- 8.18.0-1ubuntu2
- 8.18.0-1ubuntu2.1
- Affected ranges
- ECOSYSTEM: < 8.18.0-1ubuntu2.2
Update to 8.18.0-1ubuntu2.2