Cyber Resilience

CVE-2021-0270

High

Published: 22 April 2021

Published
22 April 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0033 56.6th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-0270 is a high-severity Race Condition (CWE-362) vulnerability in Juniper Junos. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 43.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

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(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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

juniper
junos
18.1

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-362

Accurate timestamps from internal clocks enable detection of race conditions by providing reliable event ordering in audit logs.

addresses: CWE-362

Coordination of concurrent security activities reduces the probability that shared resources will be accessed simultaneously without proper synchronization.

addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

References