# CVE-2026-43630: llama.cpp b4882-b8487 Out-of-Bounds Read Information Disclosure

> Attackers with write access to slot directories can trigger out-of-bounds reads to leak heap data and defeat ASLR in llama.cpp.

- **Severity:** Medium 6.3 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/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:** Not needed
- **Fix available:** Yes
- **Published:** 6 Aug 2026
- **Updated:** 22 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-43630, GHSA-27j8-r4f8-8v3x, UBUNTU-CVE-2026-43630

## What is CVE-2026-43630?

CVE-2026-43630 is a medium-severity vulnerability in ggml-org llama.cpp, published on 6 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

llama.cpp builds b4882 before b8487 contain an out-of-bounds read vulnerability in the recurrent memory state restore path that allows attackers with write access to the slot save directory to read memory past the end of the allocated cells array. Attackers can craft a malicious slot file with an oversized seq_id value to trigger an out-of-bounds read that leaks heap data including pointer values into server logs, defeating ASLR protections and facilitating further exploitation.

Weakness: CWE-209 (Generation of Error Message Containing Sensitive Information), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-43630?

It affects 1 product.


Products: Ggml Llama.cpp.

## How do I fix CVE-2026-43630?

Apply the vendor's patch.

## Is CVE-2026-43630 being exploited?

There is no known exploitation of CVE-2026-43630 in the wild and no public exploit code.

## Other vulnerabilities in ggml-org llama.cpp

- [CVE-2024-42479](https://insights.sbomify.com/CVE-2024-42479/): llama.cpp allows write-what-where in rpc_server::set_tensor (critical 10.0)
- [CVE-2026-34159](https://insights.sbomify.com/CVE-2026-34159/): llama.cpp: Unauthenticated RCE via GRAPH_COMPUTE buffer=0 bypass in llama.cpp RPC backend (critical 9.8)
- [CVE-2026-43629](https://insights.sbomify.com/CVE-2026-43629/): llama.cpp b4882–b9058 Buffer Overflow in KV Cache State Restore (critical 9.2)
- [CVE-2026-43631](https://insights.sbomify.com/CVE-2026-43631/): llama.cpp b7492–b9060 Use-After-Free RCE via llama-server (critical 9.2)
- [CVE-2026-43632](https://insights.sbomify.com/CVE-2026-43632/): llama.cpp b7492–b9060 Use-After-Free in Tokenization Endpoints (critical 9.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-43630 and fix it if it is affected.

What it is: CVE-2026-43630 is a medium-severity vulnerability in ggml-org llama.cpp, published on 6 Aug 2026. 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-2026-43630 in the wild and no public exploit code.

Affected product: ggml-org llama.cpp. 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-2026-43630/ (Markdown: https://insights.sbomify.com/CVE-2026-43630/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-43630
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-43630
- OSV: https://osv.dev/vulnerability/CVE-2026-43630

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-43630/
Summaries are generated and may contain mistakes; the official description above is the record.