# CVE-2023-7340: Wazuh authd service (os_auth) Heap-based Buffer Overflow

> Attackers can cause a denial of service in the Wazuh authentication daemon by sending specially crafted input that triggers a heap-based buffer overflow.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 27 Mar 2026
- **Updated:** 15 Jul 2026
- **Also known as:** GHSA-vp8c-mm4j-2g97

## What is CVE-2023-7340?

CVE-2023-7340 is a medium-severity memory corruption vulnerability in Wazuh Wazuh, published on 27 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Wazuh authd contains a heap-buffer overflow vulnerability that allows attackers to cause memory corruption and malformed heap data by sending specially crafted input. Attackers can exploit this vulnerability to trigger a denial of service condition, resulting in low availability impact to the authentication daemon.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2023-7340?

It affects 1 product.


Products: Wazuh Wazuh.

## How do I fix CVE-2023-7340?

No fix has been published for CVE-2023-7340 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-7340 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-7340 exists.

## Other vulnerabilities in Wazuh Wazuh

- [CVE-2025-24016](https://insights.sbomify.com/CVE-2025-24016/): Wazuh Server Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2024-32038](https://insights.sbomify.com/CVE-2024-32038/): Wazuh Analysis Engine Event Decoder Heap-based Buffer Overflow Remote Code Execution Vulnerability (critical 9.8)
- [CVE-2021-44079](https://insights.sbomify.com/CVE-2021-44079/): Command injection in n/a (critical 9.8)
- [CVE-2024-1243](https://insights.sbomify.com/CVE-2024-1243/): Remote code execution and local privilege escalation in Wazuh Windows agent via NetNTLMv2 hash theft (critical 9.5)
- [CVE-2026-61800](https://insights.sbomify.com/CVE-2026-61800/): Wazuh cluster worker file sync allows arbitrary file write under /var/ossec (incomplete fix for CVE-2026-30893) (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-7340 and fix it if it is affected.

What it is: CVE-2023-7340 is a medium-severity memory corruption vulnerability in Wazuh Wazuh, published on 27 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-7340 exists.

Affected product: Wazuh Wazuh. 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-2023-7340/ (Markdown: https://insights.sbomify.com/CVE-2023-7340/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-7340
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-7340
- OSV: https://osv.dev/vulnerability/CVE-2023-7340

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-7340/
Summaries are generated and may contain mistakes; the official description above is the record.