Product Affected

This issue affects all versions of Junos OS on MX Series with MS-MPC.
Medium

Problem

An Improper Resource Shutdown or Release vulnerability in the SIP ALG of Juniper Networks Junos OS on MX Series with MS-MPC allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).

When an MX Series device with an MS-MPC is configured with two or more service sets which are both processing SIP calls, a specific sequence of call events will lead to a crash and restart of the MS-MPC.

This issue affects Junos OS:

  • all versions before 21.2R3-S9,
  • 21.4 versions from 21.4R1,
  • 22.2 versions before 22.2R3-S6,
  • 22.4 versions before 22.4R3-S6.

 

As the MS-MPC is EoL after Junos OS 22.4, later versions are not affected.

This issue does not affect MX-SPC3 or SRX Series devices.

 

To be affected by this issue two or more service sets need to be present:

[ services service-set <set1> ... ]
[ services service-set <set2> ... ]

 

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

 

This issue was seen during production usage.

Solution

The following software releases have been updated to resolve this specific issue: 21.2R3-S9, 22.2R3-S6, 22.4R3-S6, and all subsequent releases.

 

This issue is being tracked as 1806872 which is visible on the Customer Support website.

 

Note: Juniper SIRT's policy is not to evaluate releases which are beyond End of Engineering (EOE) or End of Life (EOL).

Workaround

There are no known workarounds for this issue.

To reduce the risk of exploitation customers not requiring the SIP ALG functionality could explicitly disable it (in case it's by default enabled) by configuring:

[ security alg sip disable ]

Severity Assessment

Information for how Juniper Networks uses CVSS can be found at KB 16446 [juniper.net] "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories."

Modification History

2025-07-09: Initial Publication

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