CVE-2026-49840

{"id": "CVE-2026-49840", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.1, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 5.2, "exploitabilityScore": 3.9}]}, "published": "2026-06-09T17:17:47.703", "references": [{"url": "https://github.com/signalwire/freeswitch/releases/tag/v1.11.1", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/signalwire/freeswitch/security/advisories/GHSA-g597-9fgg-ghg9", "tags": ["Third Party Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-122"}, {"lang": "en", "value": "CWE-195"}, {"lang": "en", "value": "CWE-787"}]}], "descriptions": [{"lang": "en", "value": "FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to version 1.11.1, esl_recv_event() parses Content-Length with atol() and passes the result straight to malloc(len + 1) with no sign or magnitude check. A malicious or man-in-the-middle ESL peer can send a frame with a negative Content-Length to corrupt the heap of, or crash, any process linked against libesl, before the client has authenticated to that peer. This issue has been patched in version 1.11.1."}], "lastModified": "2026-06-10T15:06:24.257", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:freeswitch:freeswitch:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E8AED0D0-D5A1-4AA1-9CAE-13830B74CAC5", "versionEndExcluding": "1.11.1"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}