{"id":"CVE-2026-33780","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-33780","generatedAt":"2026-10-28T01:10:32.297Z","title":"A Missing Release of Memory after Effective Lifetime vulnerability in the Layer 2 Address Learning Daemon (l2ald) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause a memory leak ultimately leading to…","description":"A Missing Release of Memory after Effective Lifetime vulnerability in the Layer 2 Address Learning Daemon (l2ald) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause a memory leak ultimately leading to a Denial of Service (DoS).\n\n\n\nIn an EVPN-MPLS scenario, routes learned from remote multi-homed Provider Edge (PE) devices are programmed as ESI routes. Due to a logic issue in the l2ald memory management, memory allocated for these routes is not released when there is churn for these routes. As a result, memory leaks in the l2ald process which will ultimately lead to a crash and restart of l2ald.\n\nUse the following command to monitor the memory consumption by l2ald:\n\nuser@device> show system process extensive | match \"PID|l2ald\" \n\n\n\nThis issue affects:\n\nJunos OS:\n\n\n\n  *  all versions before 22.4R3-S5,\n  *  23.2 versions before 23.2R2-S3,\n  *  23.4 versions before 23.4R2-S4,\n  *  24.2 versions before 24.2R2;\n\n\n\n\nJunos OS Evolved:\n\n\n\n  *  all versions before 22.4R3-S5-EVO,\n  *  23.2 versions before 23.2R2-S3-EVO,\n  *  23.4 versions before 23.4R2-S4-EVO,\n  *  24.2 versions before 24.2R2-EVO.","published":"2026-04-09T22:16:27.000Z","lastModified":"2026-10-26T22:10:00.000Z","status":"Analyzed","sourceIdentifier":"sirt@juniper.net","cvss":{"version":"4.0","score":7.1,"severity":"HIGH","vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-401"],"affected":["juniper/junos","juniper/junos os evolved"],"epss":{"score":0.00173,"percentile":0.06683,"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":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.17%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://kb.juniper.net/JSA107819","tags":["Vendor Advisory"],"source":"sirt@juniper.net"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-33780","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."}