CVE-2026-40685

{"id": "CVE-2026-40685", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "cve@mitre.org", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 4.2, "exploitabilityScore": 2.2}, {"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}]}, "published": "2026-04-30T22:16:25.633", "references": [{"url": "https://code.exim.org/exim/exim/commit/9fdc057e71b87c87a0d3d2288b2810a0efaaba57", "tags": ["Patch"], "source": "cve@mitre.org"}, {"url": "https://exim.org/static/doc/security/CVE-2026-40685.txt", "tags": ["Broken Link"], "source": "cve@mitre.org"}, {"url": "https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40685.assessment", "tags": ["Vendor Advisory"], "source": "cve@mitre.org"}, {"url": "https://www.openwall.com/lists/oss-security/2026/04/30/21", "tags": ["Mailing List", "Third Party Advisory"], "source": "cve@mitre.org"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "cve@mitre.org", "description": [{"lang": "en", "value": "CWE-684"}]}, {"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-787"}]}], "descriptions": [{"lang": "en", "value": "In Exim before 4.99.2, when JSON lookup is enabled, an out-of-bounds heap write can occur when a JSON operator encounters malformed JSON in an untrusted header, because of an incorrect implementation of \\ skipping."}], "lastModified": "2026-05-01T17:51:06.830", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E48EAA99-95DA-4695-BBEA-16D09AA0A508", "versionEndExcluding": "4.99.2"}], "operator": "OR"}]}], "sourceIdentifier": "cve@mitre.org"}