dbcve.org
JunosOperating system · Juniper

CVE-2025-21598

HIGH · 7.5 CVSS v3.1 Published 2025-01-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Out-of-bounds read vulnerability in Juniper Networks Junos OS/Evolved routing protocol daemon (rpd) triggered by malformed BGP packets from an authenticated BGP peer. Attack requires established BGP session and packet receive trace options enabled on target device. Malformed packets can propagate through multiple ASes, enabling remote unauthenticated attackers to cause DoS by crashing rpd.

MitigationUpgrade to fixed Junos OS/Evolved versions per vendor advisory, or disable packet receive trace options as interim workaround if BGP sessions remain active.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
JunosOperating system
Affected:= 21.2= 21.4= 22.2= 22.3= 22.4= 23.2= 23.4= 24.2
Junos Os EvolvedOperating system
Affected:= 21.4= 22.2= 22.3= 22.4= 23.2= 23.4= 24.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check Junos OS/Evolved version
    Run 'show version' or 'show version detail' to display the installed Junos version. Compare the version number to the affected versions: 21.2, 21.4, 22.2, 22.3, 22.4, 23.2, 23.4, 24.2 for Junos; 21.4, 22.2, 22.3, 22.4, 23.2, 23.4, 24.2 for Junos Evolved.
    Affected if Running any version listed in the affected versions for your product (Junos or Junos Evolved)
  2. Verify BGP protocol is configured
    Run 'show configuration protocols bgp' to check if BGP is configured on the device.
    Affected if BGP is configured in the device configuration
  3. Check for packet receive trace options on BGP
    Run 'show configuration protocols bgp | display set' and look for 'traceoptions' with 'flag receive' or 'packet' settings under the BGP configuration. Alternatively, check 'show configuration routing-options traceoptions' for global receive trace options that may affect BGP.
    Affected if Packet receive trace options (traceoptions with flag receive or packet) are enabled for BGP or globally
  4. Check for established BGP peers
    Run 'show bgp summary' or 'show bgp neighbor' to display BGP peer status and determine if any BGP sessions are established.
    Affected if One or more BGP peers are established or configured to establish connections

You are affected if you run an affected Junos/Junos Evolved version AND have BGP configured AND have packet receive trace options enabled AND have (or could have) established BGP peers.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to fixed Junos OS/Evolved versions per vendor advisory, or disable packet receive trace options as interim workaround if BGP sessions remain active.

Recommended fix High confidence

For Junos OS: upgrade to 21.2R3-S9, 21.4R3-S9, 22.2R3-S5, 22.3R3-S4, 22.4R3-S5, 23.2R2-S2, 23.4R2-S1, 24.2R1-S1, or 24.2R2. For Junos OS Evolved: upgrade to 21.4R3-S9-EVO, 22.2R3-S5-EVO, 22.3R3-S4-EVO, 22.4R3-S5-EVO, 23.2R2-S2-EVO, 23.4R2-S1-EVO, 24.2R1-S2-EVO, or 24.2R2-EVO.

  1. 1. Identify the current Junos OS or Junos OS Evolved version running on the device using `show version`
  2. 2. Determine which fixed release corresponds to your current version based on the upgrade path below
  3. 3. Schedule a maintenance window as upgrading the routing daemon may cause brief service disruption
  4. 4. Download the appropriate fixed Junos software package from the Juniper Networks support portal
  5. 5. Upload the software package to the device using `file copy` or USB transfer
  6. 6. Install the software package using `request system software add <package_name>` for Junos OS, or `request system software evolve` for Junos OS Evolved
  7. 7. Reboot the device using `request system reboot` to complete the installation
  8. 8. After reboot, verify the new version is installed using `show version`
Caveat Standard Junos upgrade risks apply - ensure backups and failover configurations are in place before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Junos Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-21598 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-21598 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data