{"cve":"CVE-2021-0270","nvd":{"published":"2021-04-22T20:15:10.017","modified":"2026-06-17T03:29:40.087","status":"Modified","description":"On PTX Series and QFX10k Series devices with the \"inline-jflow\" feature enabled, a use after free weakness in the Packet Forwarding Engine (PFE) microkernel architecture of Juniper Networks Junos OS may allow an attacker to cause a Denial of Service (DoS) condition whereby one or more Flexible PIC Concentrators (FPCs) may restart. As this is a race condition situation this issue become more likely to be hit when network instability occurs, such as but not limited to BGP/IGP reconvergences, and/or further likely to occur when more active \"traffic flows\" are occurring through the device. When this issue occurs, it will cause one or more FPCs to restart unexpectedly. During FPC restarts core files will be generated. While the core file is generated traffic will be disrupted. Sustained receipt of large traffic flows and reconvergence-like situations may sustain the Denial of Service (DoS) situation. This issue affects: Juniper Networks Junos OS: 18.1 version 18.1R2 and later versions prior to 18.1R3-S10 on PTX Series, QFX10K Series.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.9},"cwes":["CWE-362","CWE-416"],"references":["https://kb.juniper.net/JSA11161","https://www.juniper.net/documentation/en_US/junos/topics/task/configuration/inline-flow-monitoring-ptx.html","https://kb.juniper.net/JSA11161","https://www.juniper.net/documentation/en_US/junos/topics/task/configuration/inline-flow-monitoring-ptx.html"],"products":["juniper:junos"],"source":"nvd","synced_at":"2026-10-19T21:17:01.373894544+00:00"},"epss":{"cve":"CVE-2021-0270","score":0.00722,"percentile":0.54005,"date":"2026-11-01"},"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."]}