CVE-2026-129118 (GCVE-0-2026-129118)

Vulnerability from cvelistv5 – Published: 2026-11-13 16:23 – Updated: 2026-11-13 16:23
VLAI
Title
C-Kermit 8.0.200 before 11.1.515 Improper Certificate Hostname Matching via dNSName_cmp
Summary
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.
Severity
7.6 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
6.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
CWE
  • CWE-297 - Improper Validation of Certificate with Host Mismatch
Assigner
VulnCheck CNA
References
Impacted products
Vendor Product Version
OpenKermit C-Kermit Affected: 8.0.200 , < 11.1.515 (semver)
Create a notification for this product.
Date Public
2026-10-31 00:00
Credits
John Goerzen John Goerzen
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:github/OpenKermit/ckermit",
          "product": "C-Kermit",
          "vendor": "OpenKermit",
          "versions": [
            {
              "lessThan": "11.1.515",
              "status": "affected",
              "version": "8.0.200",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "John Goerzen"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "John Goerzen"
        }
      ],
      "datePublic": "2026-10-31T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 7.6,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          },
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        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.8,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-297",
              "description": "Improper Validation of Certificate with Host Mismatch",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-13T16:23:47.381Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Security Advisory (GHSA-5pc4-gh6q-5h4w)",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/OpenKermit/ckermit/security/advisories/GHSA-5pc4-gh6q-5h4w"
        },
        {
          "tags": [
            "patch"
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          "url": "https://github.com/OpenKermit/ckermit/commit/8c60a2bd70f5a78e77ce5d140a17e7a9cdcd5e60"
        },
        {
          "name": "C-Kermit v11.1.515 Release Notes",
          "tags": [
            "release-notes"
          ],
          "url": "https://github.com/OpenKermit/ckermit/releases/tag/v11.1.515"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/OpenKermit/ckermit/blob/v11.0.514/ck_ssl.c#L3485"
        },
        {
          "name": "VulnCheck Advisory: C-Kermit 8.0.200 before 11.1.515 Improper Certificate Hostname Matching via dNSName_cmp",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/c-kermit-8.0.200-before-11.1.515-improper-certificate-hostname-matching-via-dnsname-cmp"
        }
      ],
      "title": "C-Kermit 8.0.200 before 11.1.515 Improper Certificate Hostname Matching via dNSName_cmp",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-129118",
    "datePublished": "2026-11-13T16:23:47.381Z",
    "dateReserved": "2026-11-13T16:00:58.945Z",
    "dateUpdated": "2026-11-13T16:23:47.381Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}



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