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TI-2024-26476 Aliases CVE-2024-39542GHSA-34f4-m9rh-9x9j

Junos OS and Junos OS Evolved: A malformed CFM packet or specific transit traffic leads to FPC crash

Priority MEDIUM 44CWE-1286Published · Updated

Key facts

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

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

Summary

An Improper Validation of Syntactic Correctness of Input vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series with MPC10/11 or LC9600, MX304, and Junos OS Evolved on ACX Series and PTX Series allows an unauthenticated, network based attacker to cause a Denial-of-Service (DoS). This issue can occur in two scenarios: 1. If a device, which is configured with SFLOW and ECMP, receives specific valid transit traffic, which is subject to sampling, the packetio process crashes, which in turn leads to an evo-aftman crash and causes the FPC to stop working until it is restarted. (This scenario is only applicable to PTX but not to ACX or MX.) 2. If a device receives a malformed CFM packet on an interface configured with CFM, the packetio process crashes, which in turn leads to an evo-aftman crash and causes the FPC to stop working until it is restarted. Please note that the CVSS score is for the formally more severe issue 1. The CVSS score for scenario 2. is: 6.5 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) This issue affects Junos OS: * All versions before 21.2R3-S4, * 21.4 versions before 21.4R2, * 22.2 versions before 22.2R3-S2;  Junos OS Evolved: * All versions before 21.2R3-S8-EVO, * 21.4 versions before 21.4R2-EVO.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00473 41st percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 21.2R3-S4, 21.4R2, 22.2R2-S1 +1Junos OS Evolved (Juniper Networks): 21.2R3-S8-EVO, 21.4R2-EVO

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 OSbefore 21.2R3-S4; 21.4 to before 21.4R2; 22.2 to before 22.2R2-S1, 22.2R321.2R3-S4, 21.4R2, 22.2R2-S1, 22.2R3Patch availableCNA
JuniperJunos OS Evolvedbefore 21.2R3-S8-EVO; 21.4 to before 21.4R2-EVO21.2R3-S8-EVO, 21.4R2-EVOPatch availableCNA
  • Junos OS VendorJuniper Affected before 21.2R3-S4; 21.4 to before 21.4R2; 22.2 to before 22.2R2-S1, 22.2R3 Fixed in 21.2R3-S4, 21.4R2, 22.2R2-S1, 22.2R3 Patch available CNA
  • Junos OS Evolved VendorJuniper Affected before 21.2R3-S8-EVO; 21.4 to before 21.4R2-EVO Fixed in 21.2R3-S8-EVO, 21.4R2-EVO Patch available CNA

CPE configurations NVD · 28

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:21.4:-:*:*:*:*:*:*21.4VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r1:*:*:*:*:*:*21.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r1-s1:*:*:*:*:*:*21.4 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r1-s2:*:*:*:*:*:*21.4 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:-:*:*:*:*:*:*22.2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:r1:*:*:*:*:*:*22.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:r1-s1:*:*:*:*:*:*22.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:r1-s2:*:*:*:*:*:*22.2 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:r2:*:*:*:*:*:*22.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:-:*:*:*:*:*:*21.2VulnerableJuniper
  • cpe:2.3:o:juniper:junos:21.4:-:*:*:*:*:*:* Versions 21.4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r1:*:*:*:*:*:* Versions 21.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r1-s1:*:*:*:*:*:* Versions 21.4 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r1-s2:*:*:*:*:*:* Versions 21.4 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:-:*:*:*:*:*:* Versions 22.2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:r1:*:*:*:*:*:* Versions 22.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:r1-s1:*:*:*:*:*:* Versions 22.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:r1-s2:*:*:*:*:*:* Versions 22.2 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:r2:*:*:*:*:*:* Versions 22.2 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:-:*:*:*:*:*:* Versions 21.2 Vulnerable ·Juniper
Show 18 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos_os_evolved:21.2:r1:*:*:*:*:*:*21.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r1-s1:*:*:*:*:*:*21.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r1-s2:*:*:*:*:*:*21.2 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r2:*:*:*:*:*:*21.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r2-s1:*:*:*:*:*:*21.2 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r2-s2:*:*:*:*:*:*21.2 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r3:*:*:*:*:*:*21.2 r3VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s1:*:*:*:*:*:*21.2 r3-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s2:*:*:*:*:*:*21.2 r3-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s3:*:*:*:*:*:*21.2 r3-s3VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s4:*:*:*:*:*:*21.2 r3-s4VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s5:*:*:*:*:*:*21.2 r3-s5VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s6:*:*:*:*:*:*21.2 r3-s6VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s7:*:*:*:*:*:*21.2 r3-s7VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:-:*:*:*:*:*:*21.4VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r1:*:*:*:*:*:*21.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s1:*:*:*:*:*:*21.4 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s2:*:*:*:*:*:*21.4 r1-s2VulnerableJuniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r1:*:*:*:*:*:* Versions 21.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r1-s1:*:*:*:*:*:* Versions 21.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r1-s2:*:*:*:*:*:* Versions 21.2 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r2:*:*:*:*:*:* Versions 21.2 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r2-s1:*:*:*:*:*:* Versions 21.2 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r2-s2:*:*:*:*:*:* Versions 21.2 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r3:*:*:*:*:*:* Versions 21.2 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s1:*:*:*:*:*:* Versions 21.2 r3-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s2:*:*:*:*:*:* Versions 21.2 r3-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s3:*:*:*:*:*:* Versions 21.2 r3-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s4:*:*:*:*:*:* Versions 21.2 r3-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s5:*:*:*:*:*:* Versions 21.2 r3-s5 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s6:*:*:*:*:*:* Versions 21.2 r3-s6 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.2:r3-s7:*:*:*:*:*:* Versions 21.2 r3-s7 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:-:*:*:*:*:*:* Versions 21.4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r1:*:*:*:*:*:* Versions 21.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s1:*:*:*:*:*:* Versions 21.4 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s2:*:*:*:*:*:* Versions 21.4 r1-s2 Vulnerable ·Juniper

Remediation

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 21.2R3-S4, 21.4R2, 22.2R2-S1, 22.2R3
  • Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 21.2R3-S8-EVO, 21.4R2-EVO

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-39542
  2. 2026-10-03 Alias added: GHSA-34f4-m9rh-9x9j

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-2015-04610 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
  • TI-2023-18644 Junos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload and download arbitrary files KEVCVSS 3.1MEDIUM 5.3
  • TI-2023-18640 Junos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary files KEVCVSS 3.1MEDIUM 5.3
See all 792 →

Sources

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