A flaw in the packet forwarding engine of Juniper Networks Junos OS causes a memory leak when high session churn occurs with certain application services such as ALGs, IDP/DPI, APPID, SECINTEL, AAMW or AppQoE. The leak exhausts PFE memory, resulting in traffic processing failures and a complete loss of service. The weakness corresponds to CWE-401, Memory Leak.

The vulnerability affects Junos OS on SRX series and MX series devices equipped with SPC3. Specifically it impacts SRX4000 Series, SRX5000 Series with SPC3, and MX Series with SPC3. Affected software versions include all releases prior to 23.4R2‑S7 in the 23.4 line, all releases before 24.2R2‑S3 in the 24.2 line, releases before 24.4R2‑S3 in the 24.4 line, and releases before 25.2R1‑S2 and 25.2R2 in the 25.2 line.

The CVSS score of 8.7 indicates high severity. The exploit is network‑based, unauthenticated and requires only an attacker who can generate rapid connection churn while the specified application services are enabled. The EPSS score of 0.00374 indicates a very low but non‑zero likelihood of exploitation, which, coupled with the lack of a known workaround and the potential for a complete denial of service, makes the risk significant. The vulnerability is not listed in CISA’s KEV catalog. Attackers can leverage the memory exhaustion to disrupt traffic, potentially affecting all sessions handled by the device.