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TI-2026-74219 Aliases CVE-2026-101994

Malformed ICCP message in Junos OS l2ald leaks heap memory or crashes

Priority LOW 31CWE-130Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
Low · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Juniper Networks Junos OS and Junos OS Evolved are affected in releases before the fixed versions listed for each train. An improper handling of length parameter inconsistency (CWE-130) in the l2ald daemon lets a malformed MC-LAG ICCP message disclose heap memory or cause a denial of service. An attacker who can control or impersonate a configured MC-LAG ICCP peer can trigger this.

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

Description from the CNA

An Improper Handling of Length Parameter Inconsistency vulnerability in the l2ald daemon of Juniper Networks Junos OS and Junos OS Evolved allows an attacker who can control or impersonate a configured MC-LAG ICCP peer to disclose process heap memory or cause a denial of service via a malformed ICCP message.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00278 20th percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5 +4Junos OS Evolved (Juniper Networks): 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO +6

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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 OSbefore 23.2R2-S7.7; 23.4 to before 23.4R2-S8.13; 24.2 to before 24.2R2-S5.5; 24.4 to before 24.4R2-S5; 25.2 to before 25.2R2-S2; 25.4 to before 25.4R1-S3; 26.2 to before 26.2R1-S223.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-S2Patch availableCNA
JuniperJunos OS Evolvedbefore 23.2R2-S7.7-EVO; 23.4 to before 23.4R2-S8.11-EVO; 24.2 to before 24.2R2-S5.6-EVO; 24.4 to before 24.4R2-S5-EVO; 25.2 to before 25.2R2-S2-EVO; 25.4 to before 25.4R1-S3-EVO; 26.2 to before 26.2R1-S2-EVO; 23.4X100; 25.2X100 to before 25.2X100-D35-EVO; 25.4X300 to before 25.4X300-D40-EVO23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO, 25.4X300-D40-EVOPatch availableCNA
  • Junos OS VendorJuniper Affected before 23.2R2-S7.7; 23.4 to before 23.4R2-S8.13; 24.2 to before 24.2R2-S5.5; 24.4 to before 24.4R2-S5; 25.2 to before 25.2R2-S2; 25.4 to before 25.4R1-S3; 26.2 to before 26.2R1-S2 Fixed in 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-S2 Patch available CNA
  • Junos OS Evolved VendorJuniper Affected before 23.2R2-S7.7-EVO; 23.4 to before 23.4R2-S8.11-EVO; 24.2 to before 24.2R2-S5.6-EVO; 24.4 to before 24.4R2-S5-EVO; 25.2 to before 25.2R2-S2-EVO; 25.4 to before 25.4R1-S3-EVO; 26.2 to before 26.2R1-S2-EVO; 23.4X100; 25.2X100 to before 25.2X100-D35-EVO; 25.4X300 to before 25.4X300-D40-EVO Fixed in 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO, 25.4X300-D40-EVO Patch available CNA

CPE names Threatist (inferred) · 2

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

Remediation

Upgrade Junos OS to 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3 or 26.2R1-S2. Upgrade Junos OS Evolved to 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO or 25.4X300-D40-EVO. The sources list no fixed version for Junos OS Evolved 23.4X100.

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

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-S2
  • Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO, 25.4X300-D40-EVO

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    Juniper Networks Junos OS, Junos OS Evolved — supportportal.juniper.net/JSA112187

    106 records Highest priority Priority MEDIUM 53 MEDIUM, 53 LOW

    Other records, highest priority first

    • TI-2026-74351 Stack overflow in Juniper Junos OS J-Web allows code executionPriority MEDIUM 49
    • TI-2026-74350 Stack-based buffer overflow in Junos OS rpd enables code executionPriority MEDIUM 49
    • TI-2026-74339 Improper authentication in Junos OS J-Web allows device takeoverPriority MEDIUM 49

Timeline

  1. 2026-10-15 Threatist record created from CVE-2026-101994
  2. 2026-10-16 Priority changed: MEDIUM → LOW
  3. 2026-10-16 CISA SSVC decision points changed

References

  • 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