# CVE-2023-3748: Inifinite loop in babld message parsing may cause dos

> An attacker can cause a denial of service in FRRouting by sending specially crafted babeld hello messages that trigger an infinite loop.

- **Severity:** Low 3.5 (`CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Jul 2023
- **Updated:** 27 Sep 2024
- **Also known as:** DEBIAN-CVE-2023-3748, GHSA-w8cg-4xhg-9fgw

## What is CVE-2023-3748?

CVE-2023-3748 is a low-severity denial of service vulnerability in Fedora, published on 24 Jul 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in FRRouting when parsing certain babeld unicast hello messages that are intended to be ignored. This issue may allow an attacker to send specially crafted hello messages with the unicast flag set, the interval field set to 0, or any TLV that contains a sub-TLV with the Mandatory flag set to enter an infinite loop and cause a denial of service.

Weakness: CWE-835 (Loop with Unreachable Exit Condition)

## Which versions are affected by CVE-2023-3748?

It affects 1 product.


Products: Frrouting Frrouting.

## How do I fix CVE-2023-3748?

Apply the vendor's patch.

## Is CVE-2023-3748 being exploited?

There is no known exploitation of CVE-2023-3748 in the wild and no public exploit code.

## Other vulnerabilities in Fedora

- [CVE-2024-44070](https://insights.sbomify.com/CVE-2024-44070/): Denial of service in n/a (critical 9.8)
- [CVE-2023-38406](https://insights.sbomify.com/CVE-2023-38406/): bgpd/bgp_flowspec.c in FRRouting (FRR) before 8.4.3 mishandles an nlri length of zero, aka a "flowspec overflow." (critical 9.8)
- [CVE-2022-37035](https://insights.sbomify.com/CVE-2022-37035/): Use after free in n/a (high 8.1)
- [CVE-2022-26127](https://insights.sbomify.com/CVE-2022-26127/): Memory corruption in FRRouting (high 7.8)
- [CVE-2022-26128](https://insights.sbomify.com/CVE-2022-26128/): Memory corruption in FRRouting (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-3748 and fix it if it is affected.

What it is: CVE-2023-3748 is a low-severity denial of service vulnerability in Fedora, published on 24 Jul 2023. 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-2023-3748 in the wild and no public exploit code.

Affected product: Fedora. 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-2023-3748/ (Markdown: https://insights.sbomify.com/CVE-2023-3748/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-3748
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-3748
- OSV: https://osv.dev/vulnerability/CVE-2023-3748

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-3748/
Summaries are generated and may contain mistakes; the official description above is the record.