{"id":"CVE-2019-11940","url":"https://www.cyber-defence.io/tools/cve/CVE-2019-11940","generatedAt":"2026-10-28T23:57:48.084Z","title":"In the course of decompressing HPACK inside the HTTP2 protocol, an unexpected sequence of header table resize operations can place the header table into a corrupted state, leading to a use-after-free condition and undefined behavior.","description":"In the course of decompressing HPACK inside the HTTP2 protocol, an unexpected sequence of header table resize operations can place the header table into a corrupted state, leading to a use-after-free condition and undefined behavior. This issue affects Proxygen from v0.29.0 until v2017.04.03.00.","published":"2019-12-04T17:16:44.000Z","lastModified":"2026-06-17T02:13:53.000Z","status":"Modified","sourceIdentifier":"cve-assign@fb.com","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-416"],"affected":["facebook/proxygen"],"epss":{"score":0.01364,"percentile":0.71651,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (1.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/facebook/proxygen/commit/f43b134cc5c19d8532e7fb670a1c02e85f7a8d4f","tags":["Patch","Third Party Advisory"],"source":"cve-assign@fb.com"},{"url":"https://www.facebook.com/security/advisories/cve-2019-11940","tags":["Third Party Advisory"],"source":"cve-assign@fb.com"},{"url":"https://github.com/facebook/proxygen/commit/f43b134cc5c19d8532e7fb670a1c02e85f7a8d4f","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.facebook.com/security/advisories/cve-2019-11940","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2019-11940","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}