CVE-2026-129117
C-Kermit 8.0.200 before 11.1.515 Missing Hostname Verification in AUTHENTICATION SSL
CVSS Score
6.8
EPSS Score
0.0%
EPSS Percentile
0th
C-Kermit 8.0.200 before 11.1.515 contains an improper certificate validation vulnerability that allows machine-in-the-middle attackers to impersonate Telnet servers because ssl_reply() never calls ssl_check_server_name(). Attackers can refuse START-TLS, offer Telnet AUTHENTICATION SSL, and present any trusted CA certificate to capture user credentials and session data.
| CWE | CWE-297 |
| Vendor | openkermit |
| Product | c-kermit |
| Published | Nov 13, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None
Affected Versions
OpenKermit / C-Kermit
8.0.200 < 11.1.515
References
github.com: https://github.com/OpenKermit/ckermit/security/advisories/GHSA-5pc4-gh6q-5h4w github.com: https://github.com/OpenKermit/ckermit/commit/0008b429e4fadc8ecfd3d7d661fd55d72e26d527 github.com: https://github.com/OpenKermit/ckermit/releases/tag/v11.1.515 github.com: https://github.com/OpenKermit/ckermit/blob/v11.0.514/ck_ssl.c#L3916 vulncheck.com: https://www.vulncheck.com/advisories/c-kermit-8.0.200-before-11.1.515-missing-hostname-verification-in-authentication-ssl
Credits
John Goerzen John Goerzen