Description
A flaw was found in curl. When libcurl is built with the libssh2 backend and uses a hashed known-hosts file, host key verification can mistakenly report a key mismatch as a missing key to custom verification callbacks. A remote attacker who intercepts or controls the Secure Shell (SSH) connection can exploit this flaw to make a previously pinned server appear as a new host. As a result, the application may inadvertently authenticate to an untrusted server, leading to credential exposure and the receipt of malicious data.
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
No solution or workaround provided in the CVE record.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
Sign in to view the affected projects.
Advisories
| Source | ID | Title |
|---|---|---|
Ubuntu USN |
USN-8927-1 | curl vulnerabilities |
References
History
Sun, 18 Oct 2026 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Curl
Curl curl |
|
| Vendors & Products |
Curl
Curl curl |
Sat, 17 Oct 2026 00:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | A flaw was found in curl. When libcurl is built with the libssh2 backend and uses a hashed known-hosts file, host key verification can mistakenly report a key mismatch as a missing key to custom verification callbacks. A remote attacker who intercepts or controls the Secure Shell (SSH) connection can exploit this flaw to make a previously pinned server appear as a new host. As a result, the application may inadvertently authenticate to an untrusted server, leading to credential exposure and the receipt of malicious data. | |
| Title | curl: curl: knownhost callback mismatches key as missing | |
| Weaknesses | CWE-295 | |
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
No data.
No data.
No data.
OpenCVE Enrichment
Updated: 2026-10-18T14:45:06Z
Weaknesses
-
CWE-295
Improper Certificate Validation
Ubuntu USN