{"id":"CVE-2024-21616","aliases":["EUVD-2024-19264","GHSA-355p-vp22-pp2v"],"status":"published","title":"Junos OS: MX Series and SRX Series: Processing of a specific SIP packet causes NAT IP allocation to fail","description":"An Improper Validation of Syntactic Correctness of Input vulnerability in Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an unauthenticated, network-based attacker to cause Denial of Service (DoS).\n\nOn all Junos OS MX Series and SRX Series platforms, when SIP ALG is enabled, and a specific SIP packet is received and processed, NAT IP allocation fails for genuine traffic, which causes Denial of Service (DoS). Continuous receipt of this specific SIP ALG packet will cause a sustained DoS condition.\n\nNAT IP usage can be monitored by running the following command.\n\nuser@srx\u003e show security nat resource-usage source-pool \u003csource_pool_name\u003e\n\n\nPool name: source_pool_name\n..\nAddress Factor-index Port-range Used Avail Total Usage\nX.X.X.X\n0 Single Ports 50258 52342 62464 96% \u003c\u003c\u003c\u003c\u003c\n- Alg Ports 0 2048 2048 0%\nThis issue affects:\n\nJuniper Networks Junos OS on MX Series and SRX Series\n\n\n\n  *  All versions earlier than 21.2R3-S6;\n  *  21.3 versions earlier than 21.3R3-S5;\n  *  21.4 versions earlier than 21.4R3-S5;\n  *  22.1 versions earlier than 22.1R3-S4;\n  *  22.2 versions earlier than 22.2R3-S3;\n  *  22.3 versions earlier than 22.3R3-S1;\n  *  22.4 versions earlier than 22.4R2-S2, 22.4R3;\n  *  23.2 versions earlier than 23.2R1-S1, 23.2R2.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00531,"percentile":0.45216,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-1286"],"published":"2024-01-12T00:56:20Z","modified":"2026-06-17T07:09:50Z","products":[{"vendor":"juniper","product":"junos"},{"vendor":"juniper networks","product":"junos os"}],"references":[{"url":"https://supportportal.juniper.net/JSA75757","tags":["vendor-advisory","x_transferred","Vendor Advisory"]},{"url":"https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","tags":["technical-description","x_transferred","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2024-21616"},{"url":"https://github.com/advisories/GHSA-355p-vp22-pp2v"}],"sources":{"cve":[{"id":"CVE-2024-21616","title":"Junos OS: MX Series and SRX Series: Processing of a specific SIP packet causes NAT IP allocation to fail","description":"\nAn Improper Validation of Syntactic Correctness of Input vulnerability in Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an unauthenticated, network-based attacker to cause Denial of Service (DoS).\n\nOn all Junos OS MX Series and SRX Series platforms, when SIP ALG is enabled, and a specific SIP packet is received and processed, NAT IP allocation fails for genuine traffic, which causes Denial of Service (DoS). Continuous receipt of this specific SIP ALG packet will cause a sustained DoS condition.\n\nNAT IP usage can be monitored by running the following command.\n\nuser@srx\u003e show security nat resource-usage source-pool \u003csource_pool_name\u003e\n\n\nPool name: source_pool_name\n..\nAddress Factor-index Port-range Used Avail Total Usage\nX.X.X.X\n0 Single Ports 50258 52342 62464 96% \u003c\u003c\u003c\u003c\u003c\n- Alg Ports 0 2048 2048 0%\nThis issue affects:\n\nJuniper Networks Junos OS on MX Series and SRX Series\n\n\n\n  *  All versions earlier than 21.2R3-S6;\n  *  21.3 versions earlier than 21.3R3-S5;\n  *  21.4 versions earlier than 21.4R3-S5;\n  *  22.1 versions earlier than 22.1R3-S4;\n  *  22.2 versions earlier than 22.2R3-S3;\n  *  22.3 versions earlier than 22.3R3-S1;\n  *  22.4 versions earlier than 22.4R2-S2, 22.4R3;\n  *  23.2 versions earlier than 23.2R1-S1, 23.2R2.\n\n\n\n\n\n\n","status":"published","published":"2024-01-12T00:56:20.566Z","modified":"2025-06-17T14:43:11.964Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-1286"],"updated_at":"2026-11-02T14:34:05.077718Z"}],"euvd":[{"id":"EUVD-2024-19264","description":"\nAn Improper Validation of Syntactic Correctness of Input vulnerability in Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an unauthenticated, network-based attacker to cause Denial of Service (DoS).\n\nOn all Junos OS MX Series and SRX Series platforms, when SIP ALG is enabled, and a specific SIP packet is received and processed, NAT IP allocation fails for genuine traffic, which causes Denial of Service (DoS). Continuous receipt of this specific SIP ALG packet will cause a sustained DoS condition.\n\nNAT IP usage can be monitored by running the following command.\n\nuser@srx\u003e show security nat resource-usage source-pool \u003csource_pool_name\u003e\n\n\nPool name: source_pool_name\n..\nAddress Factor-index Port-range Used Avail Total Usage\nX.X.X.X\n0 Single Ports 50258 52342 62464 96% \u003c\u003c\u003c\u003c\u003c\n- Alg Ports 0 2048 2048 0%\nThis issue affects:\n\nJuniper Networks Junos OS on MX Series and SRX Series\n\n\n\n  *  All versions earlier than 21.2R3-S6;\n  *  21.3 versions earlier than 21.3R3-S5;\n  *  21.4 versions earlier than 21.4R3-S5;\n  *  22.1 versions earlier than 22.1R3-S4;\n  *  22.2 versions earlier than 22.2R3-S3;\n  *  22.3 versions earlier than 22.3R3-S1;\n  *  22.4 versions earlier than 22.4R2-S2, 22.4R3;\n  *  23.2 versions earlier than 23.2R1-S1, 23.2R2.\n\n\n\n\n\n\n","status":"published","published":"2024-01-12T00:56:20Z","modified":"2025-06-17T14:43:11Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T20:32:22.732364Z"}],"ghsa":[{"id":"GHSA-355p-vp22-pp2v","title":"\nAn Improper Validation of Syntactic Correctness of Input vulnerability in Packet Forwarding...","description":"\nAn Improper Validation of Syntactic Correctness of Input vulnerability in Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an unauthenticated, network-based attacker to cause Denial of Service (DoS).\n\nOn all Junos OS MX Series and SRX Series platforms, when SIP ALG is enabled, and a specific SIP packet is received and processed, NAT IP allocation fails for genuine traffic, which causes Denial of Service (DoS). Continuous receipt of this specific SIP ALG packet will cause a sustained DoS condition.\n\nNAT IP usage can be monitored by running the following command.\n\nuser@srx\u003e show security nat resource-usage source-pool \u003csource_pool_name\u003e\n\n\nPool name: source_pool_name\n..\nAddress Factor-index Port-range Used Avail Total Usage\nX.X.X.X\n0 Single Ports 50258 52342 62464 96% \u003c\u003c\u003c\u003c\u003c\n- Alg Ports 0 2048 2048 0%\nThis issue affects:\n\nJuniper Networks Junos OS on MX Series and SRX Series\n\n\n\n  *  All versions earlier than 21.2R3-S6;\n  *  21.3 versions earlier than 21.3R3-S5;\n  *  21.4 versions earlier than 21.4R3-S5;\n  *  22.1 versions earlier than 22.1R3-S4;\n  *  22.2 versions earlier than 22.2R3-S3;\n  *  22.3 versions earlier than 22.3R3-S1;\n  *  22.4 versions earlier than 22.4R2-S2, 22.4R3;\n  *  23.2 versions earlier than 23.2R1-S1, 23.2R2.\n\n\n\n\n\n\n","status":"published","published":"2024-01-12T03:30:49Z","modified":"2024-01-12T03:30:56Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-1286"],"updated_at":"2026-11-02T14:55:24.003446Z"}],"nvd":[{"id":"CVE-2024-21616","description":"\nAn Improper Validation of Syntactic Correctness of Input vulnerability in Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an unauthenticated, network-based attacker to cause Denial of Service (DoS).\n\nOn all Junos OS MX Series and SRX Series platforms, when SIP ALG is enabled, and a specific SIP packet is received and processed, NAT IP allocation fails for genuine traffic, which causes Denial of Service (DoS). Continuous receipt of this specific SIP ALG packet will cause a sustained DoS condition.\n\nNAT IP usage can be monitored by running the following command.\n\nuser@srx\u003e show security nat resource-usage source-pool \u003csource_pool_name\u003e\n\n\nPool name: source_pool_name\n..\nAddress Factor-index Port-range Used Avail Total Usage\nX.X.X.X\n0 Single Ports 50258 52342 62464 96% \u003c\u003c\u003c\u003c\u003c\n- Alg Ports 0 2048 2048 0%\nThis issue affects:\n\nJuniper Networks Junos OS on MX Series and SRX Series\n\n\n\n  *  All versions earlier than 21.2R3-S6;\n  *  21.3 versions earlier than 21.3R3-S5;\n  *  21.4 versions earlier than 21.4R3-S5;\n  *  22.1 versions earlier than 22.1R3-S4;\n  *  22.2 versions earlier than 22.2R3-S3;\n  *  22.3 versions earlier than 22.3R3-S1;\n  *  22.4 versions earlier than 22.4R2-S2, 22.4R3;\n  *  23.2 versions earlier than 23.2R1-S1, 23.2R2.\n\n\n\n\n\n\n","status":"published","published":"2024-01-12T01:15:50.027Z","modified":"2026-06-17T07:09:50.927Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"}],"cwes":["CWE-1286"],"updated_at":"2026-11-02T14:09:30.070039Z"}]}}