{"id":"CVE-2026-57021","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-57021","generatedAt":"2026-10-28T02:17:40.358Z","title":"An Out-of-bounds Write vulnerability in the http-gatekeeper (http-gk) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).","description":"An Out-of-bounds Write vulnerability in the http-gatekeeper (http-gk) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).\n\nIf an SRX Series device is configured for remote-access VPN with pre-logon compliance check, a network-based attacker sending specifically formatted requests can trigger an out of bounds write leading to an http-gk process crash. This crash leads to unavailability of all services depending on the [ system services web-management ] configuration (like J-Web, remote access VPN and firewall authentication) until the process automatically restarts.\n\nThis issue affects Junos OS on SRX Series:\n\n\n  *  23.2 versions before 23.2R2-S7,\n  *  23.4 versions before 23.4R2-S8,\n  *  24.2 versions before 24.2R2-S4,\n  *  24.4 versions before 24.4R2-S4,\n  *  25.2 versions before 25.2R2,\n  *  25.4 versions before 25.4R1-S1, 25.4R2.","published":"2026-07-09T22:17:07.000Z","lastModified":"2026-10-25T15:10:00.000Z","status":"Analyzed","sourceIdentifier":"sirt@juniper.net","cvss":{"version":"4.0","score":6.9,"severity":"MEDIUM","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-787"],"affected":["juniper/junos"],"epss":{"score":0.00474,"percentile":0.40705,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.47%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://supportportal.juniper.net/JSA110081","tags":["Vendor Advisory"],"source":"sirt@juniper.net"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-57021","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."}