{"id":"CVE-2026-100822","title":"Spoofing issue in the Networking: HTTP component","summary":"Spoofing issue in the Networking: HTTP component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.","severity":"medium","cvss":5.4,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L","cwe":["CWE-451"],"vendor":"mozilla","product":"firefox","affected":["firefox < 153.4.0","firefox >= 154.0.0, < 157.0.0","thunderbird < 153.4.0","thunderbird >= 154.0, < 157.0"],"patched":["firefox 157.0.0","thunderbird 157.0"],"published":"2026-09-29","updated":"2026-10-13","sourceUpdated":"2026-10-13T16:13:02.617","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-100822","references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2051115","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-101/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-103/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","label":"security@mozilla.org"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-100822.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-100822"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2543179"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-100822"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-100822"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/#CVE-2026-100822"}],"tags":["nvd","cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.00284,"epssPercentile":0.20802,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-30T19:46:40.005806Z"},"ingestedAt":"2026-09-29T13:34:31.677Z","scores":{"nvd":5.4,"vendor":3.4},"slug":"CVE-2026-100822","body":"## Overview\n\nSpoofing issue in the Networking: HTTP component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.\n\n## Affected\n\n- `firefox < 153.4.0`\n- `firefox >= 154.0.0, < 157.0.0`\n- `thunderbird < 153.4.0`\n- `thunderbird >= 154.0, < 157.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `firefox 157.0.0`\n- `thunderbird 157.0`\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-100822.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":29.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":213977,"id":"CVE-2026-100822","ts":1790803594350,"field":"cvss","old":null,"new":"5.4"},{"seq":213976,"id":"CVE-2026-100822","ts":1790803594350,"field":"severity","old":"none","new":"medium"}]}