Junos OS: QFX10K Series: PFE crash upon receipt of specific genuine packets when sFlow is enabled

published 2023-01-12 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-26562

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 51%
public exploits: 0; none known

When sFlow is enabled and it monitors a packet forwarded via ECMP, a buffer management vulnerability in the dcpfe process of Juniper Networks Junos OS on QFX10K Series systems allows an attacker to cause the Packet Forwarding Engine (PFE) to crash and restart by sending specific genuine packets to the device, resulting in a Denial of Service (DoS) condition. The dcpfe process tries to copy more data into a smaller buffer, which overflows and corrupts the buffer, causing a crash of the dcpfe process. Continued receipt and processing of these packets will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS on QFX10K Series: All versions prior to 19.4R3-S9; 20.2 versions prior to 20.2R3-S6; 20.3 versions prior to 20.3R3-S6; 20.4 versions prior to 20.4R3-S5; 21.1 versions prior to 21.1R3-S4; 21.2 versions prior to 21.2R3-S3; 21.3 versions prior to 21.3R3-S2; 21.4 versions prior to 21.4R2-S2, 21.4R3; 22.1 versions prior to 22.1R2; 22.2 versions prior to 22.2R1-S2, 22.2R2.

Patch / fix

fixed in 1

Juniper Networks Junos OS 19.4R3-S9, 20.2R3-S6, 20.3R3-S6, 20.4R3-S5, 21.1R3-S4, 21.2R3-S3, 21.3R3-S2, 21.4R2-S2, 21.4R3, 22.1R2, 22.2R1-S2, 22.2R2

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 19 mo ago (2025-04-07)

Exploit prediction

0.65% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-120 Buffer Copy without Checking Size of Input

References

kb.juniper.net /JSA70195
vendor-advisory
juniper.net /documentation/us/en/software/junos/network-mgmt/topics/topic-map/sflow-monitoring-technology.html
product

Sources

CVE List CVE-2023-22399
NVD CVE-2023-22399

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Summary