# CVE-2025-59960: Junos OS and Junos OS Evolved: DHCP Option 82 messages from clients being passed unmodified to the DHCP server

> A DHCP client can exhaust address pools on downstream servers by sending crafted Option 82 messages in forward-only mode, causing denial of service.

- **Severity:** Medium 6.3 (`CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:N/SA:H/AU:Y/R:U/V:C/RE:M/U:Amber`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Jan 2026
- **Updated:** 16 Jan 2026
- **Also known as:** GHSA-3225-h3v6-7qv5

## What is CVE-2025-59960?

CVE-2025-59960 is a medium-severity denial of service vulnerability in Juniper Junos, published on 15 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Juniper DHCP service (jdhcpd) of Juniper Networks Junos OS and Junos OS Evolved allows a DHCP client in one subnet to exhaust the address pools of other subnets, leading to a Denial of Service (DoS) on the downstream DHCP server.

By default, the DHCP relay agent inserts its own Option 82 information when forwarding client requests, optionally replacing any Option 82 information provided by the client. When a specific DHCP DISCOVER is received in 'forward-only' mode with Option 82, the device should drop the message unless 'trust-option82' is configured. Instead, the DHCP relay forwards these packets to the DHCP server unmodified, which uses up addresses in the DHCP server's address pool, ultimately leading to address pool exhaustion.

This issue affects Junos OS: 

  *  all versions before 21.2R3-S10,
  *  from 21.4 before 21.4R3-S12,
  *  all versions of 22.2,
  *  from 22.4 before 22.4R3-S8, 
  *  from 23.2 before 23.2R2-S5, 
  *  from 23.4 before 23.4R2-S6, 
  *  from 24.2 before 24.2R2-S2, 
  *  from 24.4 before 24.4R2, 
  *  from 25.2 before 25.2R1-S1, 25.2R2.

Junos OS Evolved:

  *  all versions before 21.4R3-S12-EVO, 
  *  all versions of 22.2-EVO,
  *  from 22.4 before 22.4R3-S8-EVO, 
  *  from 23.2 before 23.2R2-S5-EVO, 
  *  from 23.4 before 23.4R2-S6-EVO, 
  *  from 24.2 before 24.2R2-S2-EVO, 
  *  from 24.4 before 24.4R2-EVO, 
  *  from 25.2 before 25.2R1-S1-EVO, 25.2R2-EVO.

Weakness: CWE-754 (Improper Check for Unusual or Exceptional Conditions)

## Which versions are affected by CVE-2025-59960?

It affects 2 products.


Products: Juniper Junos, Juniper Junos Os Evolved.

## How do I fix CVE-2025-59960?

No fix has been published for CVE-2025-59960 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-59960 being exploited?

There is no known exploitation of CVE-2025-59960 in the wild and no public exploit code.

## Other vulnerabilities in Juniper Junos

- [CVE-2023-36845](https://insights.sbomify.com/CVE-2023-36845/): Juniper Junos OS EX Series and SRX Series PHP External Variable Modification (critical 9.8, exploited in the wild)
- [CVE-2020-1631](https://insights.sbomify.com/CVE-2020-1631/): Juniper Junos OS Path Traversal (high 8.8, exploited in the wild)
- [CVE-2025-21590](https://insights.sbomify.com/CVE-2025-21590/): Juniper Junos OS Improper Isolation or Compartmentalization (medium 6.7, exploited in the wild)
- [CVE-2023-36851](https://insights.sbomify.com/CVE-2023-36851/): Juniper Junos OS SRX Series Missing Authentication for Critical Function (medium 5.3, exploited in the wild)
- [CVE-2023-36844](https://insights.sbomify.com/CVE-2023-36844/): Juniper Junos OS EX Series PHP External Variable Modification (medium 5.3, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-59960 and fix it if it is affected.

What it is: CVE-2025-59960 is a medium-severity denial of service vulnerability in Juniper Junos, published on 15 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-59960 in the wild and no public exploit code.

Affected product: Juniper Junos. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-59960/ (Markdown: https://insights.sbomify.com/CVE-2025-59960/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-59960
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-59960
- OSV: https://osv.dev/vulnerability/CVE-2025-59960

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-59960/
Summaries are generated and may contain mistakes; the official description above is the record.