# CVE-2019-11495: Weak cryptography in n/a

> Insecure PRNG seeding allows brute-forcing the intra-node communication cookie, enabling remote code execution on Couchbase Server.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 10 Sep 2019
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-55q6-9vmq-6mv6

## What is CVE-2019-11495?

CVE-2019-11495 is a critical vulnerability in Couchbase Couchbase Server, published on 10 Sep 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In Couchbase Server 5.1.1, the cookie used for intra-node communication was not generated securely. Couchbase Server uses erlang:now() to seed the PRNG which results in a small search space for potential random seeds that could then be used to brute force the cookie and execute code against a remote system. This has been fixed in version 6.0.0.

Weakness: CWE-335 (Incorrect Usage of Seeds in Pseudo-Random Number Generator (PRNG))

## Which versions are affected by CVE-2019-11495?

It affects 1 product.


Products: Couchbase Couchbase Server.

## How do I fix CVE-2019-11495?

No fix has been published for CVE-2019-11495 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-11495 being exploited?

There is no known exploitation of CVE-2019-11495 in the wild and no public exploit code.

## Other vulnerabilities in Couchbase Couchbase Server

- [CVE-2024-0519](https://insights.sbomify.com/CVE-2024-0519/): Google Chromium V8 Out-of-Bounds Memory Access (high 8.8, exploited in the wild)
- [CVE-2023-3079](https://insights.sbomify.com/CVE-2023-3079/): Google Chromium V8 Type Confusion (high 8.8, exploited in the wild)
- [CVE-2023-2033](https://insights.sbomify.com/CVE-2023-2033/): Google Chromium V8 Type Confusion (high 8.8, exploited in the wild)
- [CVE-2023-49930](https://insights.sbomify.com/CVE-2023-49930/): Missing authorization in n/a (critical 9.8)
- [CVE-2023-49931](https://insights.sbomify.com/CVE-2023-49931/): Missing authorization in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-11495 and fix it if it is affected.

What it is: CVE-2019-11495 is a critical vulnerability in Couchbase Couchbase Server, published on 10 Sep 2019. 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-2019-11495 in the wild and no public exploit code.

Affected product: Couchbase Couchbase Server. 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-2019-11495/ (Markdown: https://insights.sbomify.com/CVE-2019-11495/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-11495
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-11495
- OSV: https://osv.dev/vulnerability/CVE-2019-11495

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-11495/
Summaries are generated and may contain mistakes; the official description above is the record.