# CVE-2021-31352: SRC Series: NETCONF over SSH allows negotiation of weak ciphers

> Remote attackers can exploit weak NETCONF over SSH ciphers on Juniper SRC devices to obtain sensitive information.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Oct 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-pq3v-r83j-pgg5

## What is CVE-2021-31352?

CVE-2021-31352 is a medium-severity vulnerability in Juniper Networks SRC Series, published on 19 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An Information Exposure vulnerability in Juniper Networks SRC Series devices configured for NETCONF over SSH permits the negotiation of weak ciphers, which could allow a remote attacker to obtain sensitive information. A remote attacker with read and write access to network data could exploit this vulnerability to display plaintext bits from a block of ciphertext and obtain sensitive information. This issue affects all Juniper Networks SRC Series versions prior to 4.13.0-R6.

Weakness: CWE-327 (Use of a Broken or Risky Cryptographic Algorithm), CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2021-31352?

It affects 1 product.


Products: Juniper Session and Resource Control.

## How do I fix CVE-2021-31352?

No fix has been published for CVE-2021-31352 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-31352 being exploited?

There is no known exploitation of CVE-2021-31352 in the wild and no public exploit code.

## Other vulnerabilities in Juniper Networks SRC Series

- [CVE-2008-0960](https://insights.sbomify.com/CVE-2008-0960/): Auth bypass in n/a (critical 10.0)
- [CVE-2021-31381](https://insights.sbomify.com/CVE-2021-31381/): SRC Series: A remote attacker sending a specially crafted query may cause the web server to delete files (medium 6.5)
- [CVE-2021-31380](https://insights.sbomify.com/CVE-2021-31380/): Information disclosure in SRC Series (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-31352 and fix it if it is affected.

What it is: CVE-2021-31352 is a medium-severity vulnerability in Juniper Networks SRC Series, published on 19 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-31352 in the wild and no public exploit code.

Affected product: Juniper Networks SRC Series. 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-2021-31352/ (Markdown: https://insights.sbomify.com/CVE-2021-31352/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-31352
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-31352
- OSV: https://osv.dev/vulnerability/CVE-2021-31352

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-31352/
Summaries are generated and may contain mistakes; the official description above is the record.