SRX Series and MX Series with SPC3: A high percentage of fragments might lead to high latency or packet drops

published 2022-01-19 4y ago modified 2026-06-17 4mo ago also EUVD-2022-27300

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.9%; EPSS 0.9% chance of exploitation in 30 days, percentile 60%
public exploits: 0; none known

An Insufficient Algorithmic Complexity combined with an Allocation of Resources Without Limits or Throttling vulnerability in the flow processing daemon (flowd) of Juniper Networks Junos OS on SRX Series and MX Series with SPC3 allows an unauthenticated network attacker to cause latency in transit packet processing and even packet loss. If transit traffic includes a significant percentage (> 5%) of fragmented packets which need to be reassembled, high latency or packet drops might be observed. This issue affects Juniper Networks Junos OS on SRX Series, MX Series with SPC3: All versions prior to 18.2R3; 18.3 versions prior to 18.3R3; 18.4 versions prior to 18.4R2-S9, 18.4R3; 19.1 versions prior to 19.1R2; 19.2 versions prior to 19.2R1-S1, 19.2R2.

Patch / fix

fixed in 1

Juniper Networks Junos OS 18.2R3, 18.3R3, 18.4R2-S9, 18.4R3, 19.1R2, 19.2R1-S1, 19.2R2

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Exploit prediction

0.93% chance of exploitation in the next 30 days, higher than 60% of all scored CVEs (FIRST EPSS, 2026-11-09).

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
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-407 Inefficient Algorithmic Complexity
CWE-770 Allocation of Resources Without Limits or Throttling

References

kb.juniper.net /JSA11261
vendor-advisory

Sources

CVE List CVE-2022-22153
NVD CVE-2022-22153

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