{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-49840","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-06-01T18:50:36.056Z","datePublished":"2026-06-09T16:00:56.687Z","dateUpdated":"2026-06-09T17:00:21.313Z"},"containers":{"cna":{"title":"FreeSWITCH: Pre-authentication heap buffer overflow in libesl `Content-Length` parsing","problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","description":"CWE-20: Improper Input Validation","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-122","lang":"en","description":"CWE-122: Heap-based Buffer Overflow","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-195","lang":"en","description":"CWE-195: Signed to Unsigned Conversion Error","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-787","lang":"en","description":"CWE-787: Out-of-bounds Write","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":9.1,"baseSeverity":"CRITICAL","confidentialityImpact":"NONE","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","version":"3.1"}}],"references":[{"name":"https://github.com/signalwire/freeswitch/security/advisories/GHSA-g597-9fgg-ghg9","tags":["x_refsource_CONFIRM"],"url":"https://github.com/signalwire/freeswitch/security/advisories/GHSA-g597-9fgg-ghg9"},{"name":"https://github.com/signalwire/freeswitch/releases/tag/v1.11.1","tags":["x_refsource_MISC"],"url":"https://github.com/signalwire/freeswitch/releases/tag/v1.11.1"}],"affected":[{"vendor":"signalwire","product":"freeswitch","versions":[{"version":"< 1.11.1","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-06-09T16:00:56.687Z"},"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."}],"source":{"advisory":"GHSA-g597-9fgg-ghg9","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-09T16:59:32.826404Z","id":"CVE-2026-49840","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-06-09T17:00:21.313Z"}}]}}