CVE-2026-129118

Description

C-Kermit 8.0.200 before 11.1.515 contains an improper certificate hostname validation vulnerability that allows attackers to impersonate hosts by abusing wildcard matching in dNSName_cmp() in ck_ssl.c. Attackers holding a trusted certificate with over-matching names containing asterisks, question marks, brackets, or empty labels can intercept credentials and data over Telnet, FTP, and HTTP TLS connections.

References

• https://github.com/OpenKermit/ckermit/blob/v11.0.514/ck_ssl.c#L3485
• https://github.com/OpenKermit/ckermit/commit/8c60a2bd70f5a78e77ce5d140a17e7a9cdcd5e60
• https://github.com/OpenKermit/ckermit/releases/tag/v11.1.515
• https://github.com/OpenKermit/ckermit/security/advisories/GHSA-5pc4-gh6q-5h4w
• https://www.vulncheck.com/advisories/c-kermit-8.0.200-before-11.1.515-improper-certificate-hostname-matching-via-dnsname-cmp