libcss through 0.9.2 NULL Pointer Dereference via Media-Query Parser

{
  "id": "07f7752c6f336feb5fae4f8997e75b0a7200e2d42cfa9afb336869b2e40e4911",
  "url": "https://www.cve.org/CVERecord?id=CVE-2026-116740",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "libcss through 0.9.2 NULL Pointer Dereference via Media-Query Parser",
    "summary": "libcss through 0.9.2 contains a NULL pointer dereference vulnerability in mq_parse_media_query() that allows remote attackers to crash consumers by supplying media lists ending in a comma. Attackers can serve a stylesheet whose @media or @import media list has a trailing comma, causing NetSurf or other parsers to crash.",
    "evidence": "cve:CVE-2026-116740",
    "products": [
      {
        "name": {
          "value": "libcss",
          "evidence": "/containers/cna/affected/0/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-116740",
      "aliases": [
        "CVE-2026-116740"
      ],
      "metrics": [
        {
          "format": "CVSS",
          "cvssV4_0": {
            "version": "4.0",
            "baseScore": 7.1,
            "attackVector": "NETWORK",
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "userInteraction": "PASSIVE",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "privilegesRequired": "NONE",
            "subIntegrityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "subAvailabilityImpact": "NONE",
            "vulnAvailabilityImpact": "HIGH",
            "subConfidentialityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE"
          }
        },
        {
          "format": "CVSS",
          "cvssV3_1": {
            "scope": "UNCHANGED",
            "version": "3.1",
            "baseScore": 6.5,
            "attackVector": "NETWORK",
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
            "integrityImpact": "NONE",
            "userInteraction": "REQUIRED",
            "attackComplexity": "LOW",
            "availabilityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "confidentialityImpact": "NONE"
          }
        }
      ],
      "affected": [
        {
          "repo": "https://github.com/netsurf-browser/libcss",
          "vendor": "netsurf-browser",
          "product": "libcss",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "versionType": "custom",
              "lessThanOrEqual": "0.9.2"
            }
          ],
          "packageURL": "pkg:github/netsurf-browser/libcss",
          "defaultStatus": "unaffected"
        }
      ],
      "modified": "2026-10-26T21:52:39.177Z",
      "provider": "cve",
      "references": [
        "https://github.com/netsurf-browser/libcss/commit/006ffc4096040da13690abc380e5f828ec08284d",
        "https://github.com/netsurf-browser/libcss",
        "https://github.com/netsurf-browser/libcss/blob/release/0.9.2/src/parse/mq.c#L984",
        "https://hackmd.io/@haindpwn/libcss-media-list-null-deref",
        "https://www.vulncheck.com/advisories/libcss-through-0.9.2-null-pointer-dereference-via-media-query-parser"
      ],
      "provider_metadata": {
        "cna": {
          "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
          "shortName": "VulnCheck",
          "dateUpdated": "2026-10-26T21:52:39.177Z"
        }
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-116740",
        "evidence": "/cveMetadata/cveId"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/containers/cna/metrics"
  },
  "source_id": "core-cve",
  "document_id": 353937,
  "published_at": "2026-10-26T21:52:39.177+00:00"
}