CVE-2026-57029

Summary

A Missing Synchronization vulnerability in the flow collector handler of Juniper Networks Junos OS Evolved on QFX Series allows an adjacent, unauthenticated attacker to cause a Denial-of-Service (DoS).

When the reachability of an sFlow collector changes, the corresponding next-hop entry is updated. If this update occurs simultaneously with the sFlow thread accessing the next-hop data (which is outside the attackers control), it causes the evo-pfemand process to crash, impacting all traffic forwarding until the automatic process restart has completed.

This issue affects Junos OS Evolved on QFX Series:

  • all 23.2 versions, 
  • 23.4 versions before 23.4R2-S7-EVO,
  • 24.2 versions before 24.2R2-S5-EVO,
  • 24.4 versions before 24.4R2-S3-EVO,
  • 25.2 versions before 25.2R2-EVO.

Affected Software

VendorProductVersion RangeStatus
Juniper NetworksJunos OS Evolved0 < 23.4R2-S7-EVOaffected
Juniper NetworksJunos OS Evolved24.2 < 24.2R2-S5-EVOaffected
Juniper NetworksJunos OS Evolved24.4 < 24.4R2-S3-EVOaffected
Juniper NetworksJunos OS Evolved25.2 < 25.2R2-EVOaffected

Weaknesses

  • CWE-820: CWE-820 Missing Synchronization

Workarounds

There are no known workarounds for this issue.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References