CVE-2026-9547
7.4
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Summary
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.
Affected Software
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| curl | curl | 7.69.0 < 8.14.2 | affected |
| curl | curl | 8.15.0 < 8.16.1 | affected |
| curl | curl | 8.17.0 < 8.20.1 | affected |
| curl | curl | 507cf6a13db0375eadd4655b4c64710db29e9cf2 < 0b8dbbc63c98777e4584cb9fbd71df3464008ad1 | affected |
| curl | curl | 8.20.0 | affected |
| curl | curl | 8.19.0 | affected |
| curl | curl | 8.18.0 | affected |
| curl | curl | 8.17.0 | affected |
| curl | curl | 8.16.0 | affected |
| curl | curl | 8.15.0 | affected |
| curl | curl | 8.14.1 | affected |
| curl | curl | 8.14.0 | affected |
| curl | curl | 8.13.0 | affected |
| curl | curl | 8.12.1 | affected |
| curl | curl | 8.12.0 | affected |
| curl | curl | 8.11.1 | affected |
| curl | curl | 8.11.0 | affected |
| curl | curl | 8.10.1 | affected |
| curl | curl | 8.10.0 | affected |
| curl | curl | 8.9.1 | affected |
| curl | curl | 8.9.0 | affected |
| curl | curl | 8.8.0 | affected |
| curl | curl | 8.7.1 | affected |
| curl | curl | 8.7.0 | affected |
| curl | curl | 8.6.0 | affected |
| curl | curl | 8.5.0 | affected |
| curl | curl | 8.4.0 | affected |
| curl | curl | 8.3.0 | affected |
| curl | curl | 8.2.1 | affected |
| curl | curl | 8.2.0 | affected |
| curl | curl | 8.1.2 | affected |
| curl | curl | 8.1.1 | affected |
| curl | curl | 8.1.0 | affected |
| curl | curl | 8.0.1 | affected |
| curl | curl | 8.0.0 | affected |
| curl | curl | 7.88.1 | affected |
| curl | curl | 7.88.0 | affected |
| curl | curl | 7.87.0 | affected |
| curl | curl | 7.86.0 | affected |
| curl | curl | 7.85.0 | affected |
| curl | curl | 7.84.0 | affected |
| curl | curl | 7.83.1 | affected |
| curl | curl | 7.83.0 | affected |
| curl | curl | 7.82.0 | affected |
| curl | curl | 7.81.0 | affected |
| curl | curl | 7.80.0 | affected |
| curl | curl | 7.79.1 | affected |
| curl | curl | 7.79.0 | affected |
| curl | curl | 7.78.0 | affected |
| curl | curl | 7.77.0 | affected |
| curl | curl | 7.76.1 | affected |
| curl | curl | 7.76.0 | affected |
| curl | curl | 7.75.0 | affected |
| curl | curl | 7.74.0 | affected |
| curl | curl | 7.73.0 | affected |
| curl | curl | 7.72.0 | affected |
| curl | curl | 7.71.1 | affected |
| curl | curl | 7.71.0 | affected |
| curl | curl | 7.70.0 | affected |
| curl | curl | 7.69.1 | affected |
| curl | curl | 7.69.0 | affected |
Weaknesses
- CWE-297: Improper Validation of Certificate with Host Mismatch
ADP Enrichment
CISA ADP Vulnrichment
- SSVC:
- Exploitation: poc
- Automatable: no
- Technical Impact: total
Additional References
References
- https://curl.se/docs/CVE-2026-9547.json
- https://curl.se/docs/CVE-2026-9547.html
- https://hackerone.com/reports/3751712
Feedback
Was this page helpful?
Glad to hear it! Please tell us how we can improve.
Sorry to hear that. Please tell us how we can improve.