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TI-2026-74289 Aliases CVE-2026-102081

Memory leak in Junos OS on SRX and MX Series under high session churn

Priority MEDIUM 44CWE-401Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-401.

Summary

Juniper Networks Junos OS on SRX Series and MX Series is affected in 23.4 from 23.4R2-S3 before 23.4R2-S7, 24.2 from 24.2R2 before 24.2R2-S3, 24.4 before 24.4R2-S3, and 25.2 before 25.2R1-S2, 25.2R2. Missing release of memory (CWE-401) in the packet forwarding engine makes PFE memory leak under high connections-per-second churn when application services such as ALGs or IDP/DPI are configured. An unauthenticated network attacker can exhaust this memory and cause a complete denial of service as traffic processing is impacted.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

A Missing Release of Memory after Effective Lifetime vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a complete Denial-of-Service (DoS). On SRX4000 Series, and SRX5000 Series with SPC3, and MX Series with SPC3, when one or more specific application services like ALGs, IDP/DPI, APPID, SECINTEL, AAMW or AppQoE are configured, a high connections per second churn will cause PFE memory to leak. If the memory is exhausted traffic processing will be impacted. Use the CLI command show security monitoring to monitor the memory utilization of the PFEs on the FPCs. This issue affects Junos OS on SRX Series and MX Series: * 23.4 versions from 23.4R2-S3 before 23.4R2-S7; * 24.2 versions from 24.2R2 before 24.2R2-S3; * 24.4 versions before 24.4R2-S3; * 25.2 versions before 25.2R1-S2, 25.2R2.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00374 31st percentileScored 2026-11-08
Fix Fixed Junos OS (Juniper Networks): 23.4R2-S7, 24.2R2-S3, 24.4R2-S3 +2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OS23.4R2-S3 to before 23.4R2-S7; 24.2R2 to before 24.2R2-S3; 24.4 to before 24.4R2-S3; 25.2 to before 25.2R1-S2, 25.2R223.4R2-S7, 24.2R2-S3, 24.4R2-S3, 25.2R1-S2, 25.2R2Patch availableCNA
  • Junos OS VendorJuniper Affected 23.4R2-S3 to before 23.4R2-S7; 24.2R2 to before 24.2R2-S3; 24.4 to before 24.4R2-S3; 25.2 to before 25.2R1-S2, 25.2R2 Fixed in 23.4R2-S7, 24.2R2-S3, 24.4R2-S3, 25.2R1-S2, 25.2R2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:*:*:*:*:*:*:*:*——Juniper
  • cpe:2.3:o:juniper:junos:*:*:*:*:*:*:*:* Versions — — ·Juniper

Remediation

Upgrade Junos OS to 23.4R2-S7 for 23.4, 24.2R2-S3 for 24.2, 24.4R2-S3 for 24.4, or 25.2R1-S2 or 25.2R2 for 25.2. The sources list no advisory identifier for this fix. Use the CLI command show security monitoring to check PFE memory utilization on the FPCs.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 23.4R2-S7, 24.2R2-S3, 24.4R2-S3, 25.2R1-S2, 25.2R2

Timeline

  1. 2026-10-15 Threatist record created from CVE-2026-102081

References

Advisory 1

  • TI-2023-18638 Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to… KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-01585 Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) services KEVCVSS 3.1CRITICAL 9.8
  • TI-2015-06436 Juniper ScreenOS 6.2.0r15 through 6.2.0r18, 6.3.0r12 before 6.3.0r12b, 6.3.0r13 before… KEVCVSS 3.1CRITICAL 9.8
  • TI-2022-20885 Apache Commons Text prior to 1.10.0 allows RCE when applied to untrusted input due to insecure interpolation defaults CVSS 3.1CRITICAL 9.8
  • TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
  • TI-2025-15550 Junos OS: An local attacker with shell access can execute arbitrary code KEVCVSS 4.0MEDIUM 6.7
See all 1284 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences