# CVE-2026-81883: radare2: Out-of-bounds Read at the end of string in the LUA 5.3 bytecode


- **Severity:** Low 3.3 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 22 Sep 2026
- **Updated:** 22 Sep 2026
- **Also known as:** GHSA-96m5-hvwp-674c, UBUNTU-CVE-2026-81883

## What is CVE-2026-81883?

CVE-2026-81883 is a low-severity vulnerability in Radare Radare2, published on 22 Sep 2026. 

### Official description

radare2 is a UNIX-like reverse engineering framework and command-line toolset. Prior to 6.2.0, radare2's Lua 5.3 bytecode function parser was vulnerable because the Lua 5.3 bytecode function parser read fixed function-metadata fields immediately after a function-name string without checking the remaining buffer length. The vulnerability is triggered by opening or inspecting a crafted Lua 5.3 bytecode file whose function-name string ends at the input-buffer boundary. The parser read two integers and three one-byte fields beyond the allocated input buffer. This can cause invalid parser results or process termination; no attacker-observable memory disclosure has been demonstrated. This issue is fixed in version 6.2.0.

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

## Which versions are affected by CVE-2026-81883?

It affects 1 product.


Products: Radare Radare2.

## How do I fix CVE-2026-81883?

Upgrade to a fixed version.

## Is CVE-2026-81883 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-81883 exists.

## Other vulnerabilities in Radare Radare2

- [CVE-2025-1864](https://insights.sbomify.com/CVE-2025-1864/): Buffer Overflow and Potential Code Execution in Radare2 (critical 10.0)
- [CVE-2025-1744](https://insights.sbomify.com/CVE-2025-1744/): Out-of-bounds Write in radare2 (critical 10.0)
- [CVE-2021-32494](https://insights.sbomify.com/CVE-2021-32494/): Denial of service in radare2 (critical 10.0)
- [CVE-2021-32495](https://insights.sbomify.com/CVE-2021-32495/): Use after free in radare2 (critical 10.0)
- [CVE-2024-29646](https://insights.sbomify.com/CVE-2024-29646/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-81883 and fix it if it is affected.

What it is: CVE-2026-81883 is a low-severity vulnerability in Radare Radare2, published on 22 Sep 2026. 
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-81883 exists.

Affected product: Radare Radare2. 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-2026-81883/ (Markdown: https://insights.sbomify.com/CVE-2026-81883/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-81883
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-81883
- OSV: https://osv.dev/vulnerability/CVE-2026-81883

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-81883/
Summaries are generated and may contain mistakes; the official description above is the record.