Junos OS (SRX firewalls)
CVE-2025-21598: When BGP traceoptions are configured, receipt of malformed BGP packets causes RPD to crash
An Out-of-bounds Read vulnerability in Juniper Networks Junos OS and Junos OS Evolved's routing protocol daemon (rpd) allows an unauthenticated, network-based attacker to send malformed BGP packets to a device configured with packet receive trace options enabled to crash rpd.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Junos OS 21.2R3-S8 | 21.2R3-S9 or later |
| Junos OS 21.4R3-S7 | 21.4R3-S9 or later |
| Junos OS 22.2R3-S4 | 22.2R3-S5 or later |
| Junos OS 22.3R3-S2 | 22.3R3-S4 or later |
| Junos OS 22.4R3 | 22.4R3-S5 or later |
| Junos OS 23.2R2 | 23.2R2-S2 or later |
| Junos OS 23.4R1 | 23.4R2-S1 or later |
| Junos OS 24.2R1 | 24.2R1-S1, 24.2R2 or later |
| Junos OS Evolved 21.4R3-S7-EVO | 21.4R3-S9-EVO or later |
| Junos OS Evolved 22.2R3-S4-EVO | 22.2R3-S5-EVO or later |
| Junos OS Evolved 22.3R3-S2-EVO | 22.3R3-S4-EVO or later |
| Junos OS Evolved 22.4R3-EVO | 22.4R3-S5-EVO or later |
| Junos OS Evolved 23.2R2-EVO | 23.2R2-S2-EVO or later |
| Junos OS Evolved 23.4R1-EVO | 23.4R2-S1-EVO or later |
| Junos OS Evolved 24.2R1-EVO | 24.2R1-S2-EVO, 24.2R2-EVO or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
An Out-of-bounds Read vulnerability in Juniper Networks Junos OS and Junos OS Evolved's routing protocol daemon (rpd) allows an unauthenticated, network-based attacker to send malformed BGP packets to a device configured with packet receive trace options enabled to crash rpd. This issue affects:
Junos OS:
- from 21.2R3-S8 before 21.2R3-S9,
- from 21.4R3-S7 before 21.4R3-S9,
- from 22.2R3-S4 before 22.2R3-S5,
- from 22.3R3-S2 before 22.3R3-S4,
- from 22.4R3 before 22.4R3-S5,
- from 23.2R2 before 23.2R2-S2,
- from 23.4R1 before 23.4R2-S1,
- from 24.2R1 before 24.2R1-S1, 24.2R2.
Junos OS Evolved: * from 21.4R3-S7-EVO before 21.4R3-S9-EVO, * from 22.2R3-S4-EVO before 22.2R3-S5-EVO, * from 22.3R3-S2-EVO before 22.3R3-S4-EVO, * from 22.4R3-EVO before 22.4R3-S5-EVO, * from 23.2R2-EVO before 23.2R2-S2-EVO, * from 23.4R1-EVO before 23.4R2-S1-EVO, * from 24.2R1-EVO before 24.2R1-S2-EVO, 24.2R2-EVO.
This issue requires a BGP session to be established.
This issue can propagate and multiply through multiple ASes until reaching vulnerable devices.
This issue affects iBGP and eBGP.
This issue affects IPv4 and IPv6.
An indicator of compromise may be the presence of malformed update messages in a neighboring AS which is unaffected by this issue:
For example, by issuing the command on the neighboring device: show log messages
Reviewing for similar messages from devices within proximity to each other may indicate this malformed packet is propagating: rpd[<pid>]: Received malformed update from <IP address> (External AS <AS#>) and rpd[<pid>]: Malformed Attribute
Am I affected?
This issue can occur when bgp trace options are enabled at global, group, or neighbor-level.
The following global example is provided: [protocols bgp traceoptions flag update detail] or [protocols bgp traceoptions flag receive detail] and [protocols bgp traceoptions flag update detail] [protocols bgp traceoptions flag receive detail]
The following neighbor-level example is provided: [protocols bgp group test neighbor 192.168.1.1 traceoptions flag update detail] [protocols bgp group test neighbor 192.168.1.1 traceoptions flag receive detail]
Refer to your product documentation for other examples and configurations.
Workarounds
Disabling packet tracing options will work around this issue.
There are no other available workarounds for this issue.
Exploitation
Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.