# CVE-2026-15976: CVE-2026-15976

> Attackers can execute arbitrary code by loading malicious model weights from a HuggingFace repository due to unsafe pickle deserialization.

- **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:** 30 Jul 2026
- **Updated:** 31 Jul 2026
- **Also known as:** GHSA-r344-357p-w9pp, GHSA-wf98-gv64-5wrf

## What is CVE-2026-15976?

CVE-2026-15976 is a critical unsafe deserialization vulnerability in SGLang, published on 30 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

SGLang contains a RCE vulnerability when attempting to load model weights from a HuggingFace repository, specifically within the /update_weights_from_disk, where torch.load(..., weights_only=False) fallback enables pickle deserialization of .bin files.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-15976?

It affects 1 product.


Products: Lmsys Sglang.

## How do I fix CVE-2026-15976?

No fix has been published for CVE-2026-15976 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-15976 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-15976 exists.

## Other vulnerabilities in SGLang

- [CVE-2026-15969](https://insights.sbomify.com/CVE-2026-15969/): CVE-2026-15969 (critical 9.8)
- [CVE-2026-15971](https://insights.sbomify.com/CVE-2026-15971/): CVE-2026-15971 (critical 9.8)
- [CVE-2026-7301](https://insights.sbomify.com/CVE-2026-7301/): CVE-2026-7301 (critical 9.8)
- [CVE-2026-7304](https://insights.sbomify.com/CVE-2026-7304/): CVE-2026-7304 (critical 9.8)
- [CVE-2026-5760](https://insights.sbomify.com/CVE-2026-5760/): CVE-2026-5760 (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-15976 and fix it if it is affected.

What it is: CVE-2026-15976 is a critical unsafe deserialization vulnerability in SGLang, published on 30 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-15976 exists.

Affected product: SGLang. 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-2026-15976/ (Markdown: https://insights.sbomify.com/CVE-2026-15976/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-15976
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-15976
- OSV: https://osv.dev/vulnerability/CVE-2026-15976

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-15976/
Summaries are generated and may contain mistakes; the official description above is the record.