CVE-2026-57027
published 2026-07-09CVE-2026-57027: A Missing Release of Memory after Effective Lifetime vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX Series…
PriorityP432medium6.5CVSS 3.1
AVAACLPRNUINSUCNINAH
EPSS
0.27%
18.7th percentile
A Missing Release of Memory after Effective Lifetime vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX Series devices allows an unauthenticated adjacent attacker to cause a Denial-of-Service (DoS).When sFlow is configured in a Virtual Chassis (VC) scenario with EX4100 Series or EX4400 Series devices, multicast traffic which is received on one VC member and sent out on another member leads to a memory leak and ultimately an FPC crash and restart.
The leak can be monitored by watching the continuous increase of the buffer values in the output of:
user@host> show chassis fpc
This issue affects Junos OS on EX4100 Series and EX4400:
* all versions before 23.2R2-S7,
* 23.4 versions before 23.4R2-S7,
* 24.2 versions before 24.2R2-S4,
* 24.4 versions before 24.4R2.
Affected
39 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| juniper | junos | < 23.2 | 23.2 |
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CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.07.1HIGHCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:X/RE:M/U:X
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VulDB
Juniper Junos OS up to 23.2R2-S6/23.4R2-S6/24.2R2-S3/24.4R1 Packet Forwarding Engine memory leak
vuldb·2026-07-10·CVSS 6.5
CVE-2026-57027 [MEDIUM] Juniper Junos OS up to 23.2R2-S6/23.4R2-S6/24.2R2-S3/24.4R1 Packet Forwarding Engine memory leak
A vulnerability was found in Juniper Junos OS up to 23.2R2-S6/23.4R2-S6/24.2R2-S3/24.4R1. It has been declared as problematic. Affected by this issue is some unknown functionality of the component Packet Forwarding Engine. The manipulation results in memory leak.
This vulnerability is cataloged as CVE-2026-57027. The attack must be initiated from a local position. There is no exploit available.
GHSA
A Missing Release of Memory after Effective Lifetime vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX Series devices allows an unauthenticated adjacent a
ghsa_unreviewed·2026-07-10
CVE-2026-57027 [HIGH] CWE-401 A Missing Release of Memory after Effective Lifetime vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX Series devices allows an unauthenticated adjacent a
A Missing Release of Memory after Effective Lifetime vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX Series devices allows an unauthenticated adjacent attacker to cause a Denial-of-Service (DoS).When sFlow is configured in a Virtual Chassis (VC) scenario with EX4100 Series or EX4400 Series devices, multicast traffic which is received on one VC member and sent out on another member leads to a memory leak and ultimately an FPC crash and restart.
The leak can be monitored by watching the continuous increase of the buffer values in the output of:
user@host> show chassis fpc
This issue affects Junos OS on EX4100 Series and EX4400:
* all versions before 23.2R2-S7,
* 23.4 versions before 23.4R2-S7,
* 24.2 versions before 24.2R2-S4,
* 24.4 versio
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-07-09
Published