{"id":"CVE-2023-50269","url":"https://www.cyber-defence.io/tools/cve/CVE-2023-50269","generatedAt":"2026-11-04T22:34:54.053Z","title":"Due to an Uncontrolled Recursion bug in versions 2.6 through 2.7.STABLE9, versions 3.1 through 5.9, and versions 6.0.1 through 6.5, Squid may be vulnerable to a Denial of Service attack against HTTP Request parsing.","description":"Squid is a caching proxy for the Web. Due to an Uncontrolled Recursion bug in versions 2.6 through 2.7.STABLE9, versions 3.1 through 5.9, and versions 6.0.1 through 6.5, Squid may be vulnerable to a Denial of Service attack against HTTP Request parsing. This problem allows a remote client to perform Denial of Service attack by sending a large X-Forwarded-For header when the follow_x_forwarded_for feature is configured. This bug is fixed by Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives.","published":"2023-12-14T18:15:45.000Z","lastModified":"2026-06-17T06:39:25.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-674"],"affected":["squid-cache/squid"],"epss":{"score":0.57627,"percentile":0.99084,"date":"2026-11-03","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 57.6%, higher than 99% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://www.squid-cache.org/Versions/v5/SQUID-2023_10.patch","tags":["Broken Link"],"source":"security-advisories@github.com"},{"url":"http://www.squid-cache.org/Versions/v6/SQUID-2023_10.patch","tags":["Broken Link"],"source":"security-advisories@github.com"},{"url":"https://github.com/squid-cache/squid/security/advisories/GHSA-wgq4-4cfg-c4x3","tags":["Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://lists.debian.org/debian-lts-announce/2024/01/msg00003.html","source":"security-advisories@github.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/","source":"security-advisories@github.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/","source":"security-advisories@github.com"},{"url":"https://security.netapp.com/advisory/ntap-20240119-0005/","source":"security-advisories@github.com"},{"url":"http://www.squid-cache.org/Versions/v5/SQUID-2023_10.patch","tags":["Broken Link"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.squid-cache.org/Versions/v6/SQUID-2023_10.patch","tags":["Broken Link"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/squid-cache/squid/security/advisories/GHSA-wgq4-4cfg-c4x3","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/01/msg00003.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20240119-0005/","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-50269","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."}