{"cve":"CVE-2021-28662","nvd":{"published":"2021-05-27T12:15:08.263","modified":"2026-06-17T03:46:43.673","status":"Modified","description":"An issue was discovered in Squid 4.x before 4.15 and 5.x before 5.0.6. If a remote server sends a certain response header over HTTP or HTTPS, there is a denial of service. This header can plausibly occur in benign network traffic.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-116"],"references":["http://seclists.org/fulldisclosure/2023/Oct/14","http://www.openwall.com/lists/oss-security/2023/10/11/3","http://www.squid-cache.org/Versions/v6/changesets/squid-6-051824924c709bd6162a378f746fb859454c674e.patch","https://github.com/squid-cache/squid/commit/051824924c709bd6162a378f746fb859454c674e","https://github.com/squid-cache/squid/security/advisories/GHSA-jjq6-mh2h-g39h"],"products":["debian:debian_linux","fedoraproject:fedora","squid-cache:squid"],"source":"nvd","synced_at":"2026-10-19T21:18:09.669877188+00:00"},"epss":{"cve":"CVE-2021-28662","score":0.7176,"percentile":0.99424,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}