{"schemaVersion":2,"id":"CVE-2026-109757","aliases":["DEBIAN-CVE-2026-109757"],"status":"published","duplicateOf":null,"title":null,"description":"Sandbox escape due to race condition in the Networking component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.","dates":{"published":"2026-10-13T12:29:30.583Z","modified":"2026-10-15T19:56:31.008Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":8.3,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":8.3,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":8.3,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00159,"percentile":0.0454,"severity":"low","asOf":"2026-10-15T00:00:00.000Z","change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[{"date":"2026-10-14T00:00:00.000Z","score":0.00159,"percentile":0.0453},{"date":"2026-10-15T00:00:00.000Z","score":0.00159,"percentile":0.0454}],"last30":[{"date":"2026-10-14T00:00:00.000Z","score":0.00159,"percentile":0.0453},{"date":"2026-10-15T00:00:00.000Z","score":0.00159,"percentile":0.0454}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-362","name":"Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')","description":"The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.","type":"weakness","status":"Draft","abstraction":"Class","likelihoodOfExploit":"Medium","url":"https://cwe.mitre.org/data/definitions/362.html","capec":[{"id":"CAPEC-26","name":"Leveraging Race Conditions","url":"https://capec.mitre.org/data/definitions/26.html"},{"id":"CAPEC-29","name":"Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions","url":"https://capec.mitre.org/data/definitions/29.html"}],"techniques":[],"countermeasures":[]}],"ttp":{"capecs":[{"id":"CAPEC-26","name":"Leveraging Race Conditions","url":"https://capec.mitre.org/data/definitions/26.html","weaknessIds":["CWE-362"],"techniqueIds":[]},{"id":"CAPEC-29","name":"Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions","url":"https://capec.mitre.org/data/definitions/29.html","weaknessIds":["CWE-362"],"techniqueIds":[]}],"techniques":[],"countermeasures":[],"countermeasuresByTactic":[]},"affected":[{"vendor":"debian","product":"firefox-esr","name":"firefox-esr","label":"firefox-esr","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/firefox-esr","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null},{"text":"< 153.5.0esr-1~deb12u1","noFixRecorded":false,"fixedIn":null},{"text":"< 153.5.0esr-1~deb13u1","noFixRecorded":false,"fixedIn":null}],"versionsText":"All versions (No fix recorded) | < 153.5.0esr-1~deb12u1 | < 153.5.0esr-1~deb13u1","eol":null},{"vendor":"debian","product":"thunderbird","name":"thunderbird","label":"thunderbird","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/thunderbird","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null}],"affectedCount":2,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2069910","label":"bugzilla.mozilla.org/show_bug.cgi?id=2069910","hostname":"bugzilla.mozilla.org","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","label":"www.mozilla.org/security/advisories/mfsa2026-106/","hostname":"www.mozilla.org","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-108/","label":"www.mozilla.org/security/advisories/mfsa2026-108/","hostname":"www.mozilla.org","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-109/","label":"www.mozilla.org/security/advisories/mfsa2026-109/","hostname":"www.mozilla.org","tags":[]},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-110/","label":"www.mozilla.org/security/advisories/mfsa2026-110/","hostname":"www.mozilla.org","tags":[]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-109757","label":"security-tracker.debian.org/tracker/CVE-2026-109757","hostname":"security-tracker.debian.org","tags":["Advisory"]}],"lineage":{"upstream":[],"downstream":["OPENSUSE-SU-2026:12116-1"],"duplicates":[],"related":["OPENSUSE-SU-2026:12116-1"]},"timeline":[{"kind":"published","date":"2026-10-13T12:29:30.583Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-10-15T19:56:31.008Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":33,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-16T00:40:07.181Z","stale":false,"partial":false}}