CVE-2025-21598: high-severity vulnerability in Juniper Networks Junos OS
Junos OS and Junos OS Evolved: When BGP traceoptions are configured, receipt of malformed BGP packets causes RPD to crash
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.7%
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
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/V:C/RE:M/U:Amber
Related CVEs — Juniper Networks Junos OS
In the same product, most dangerous first.
CVE-2023-36845CRITICALJunos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to control an important environment variableEPSS 95.1%KEVCVE-2023-36846MEDIUMJunos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary filesEPSS 93.5%KEVCVE-2023-36844MEDIUMJunos OS: EX Series: A PHP vulnerability in J-Web allows an unauthenticated attacker to control important environment variablesEPSS 90.0%KEVCVE-2023-36847MEDIUMJunos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary filesEPSS 83.5%KEVCVE-2020-1631HIGHOut of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) servicesEPSS 4.9%KEVCVE-2025-21590MEDIUMJunos OS: An local attacker with shell access can execute arbitrary codeEPSS 1.7%KEV