# CVE-2026-109229: SGLang denial of service via disabled image decompression protection

Source: https://junglewise.ai/threats/cve-2026-109229-sglang-through-0-5-21-contains-a-denial-of-service-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-12. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-109229 · Severity: high · CVSS 7.5 · Published 2026-10-12

SGLang is a high-performance serving framework for large language models and multimodal models. A vulnerability in SGLang through version 0.5.21 allows remote attackers to send specially crafted compressed images that cause the service to exhaust memory and become unavailable by disabling built-in protections against decompression bomb attacks. An attacker can crash the service and disrupt availability without requiring authentication.

Technologies: [SGLang Project SGLang](https://junglewise.ai/threats/technologies/sglang). Vendors: [SGLang Project](https://junglewise.ai/threats/vendors/sglang-project).

## Quick answers

**Is CVE-2026-109229 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-109229 being exploited in the wild.

**How severe is CVE-2026-109229?** High severity, with a CVSS score of 7.5, published 12 October 2026.

**Which products and versions are affected?** SGLang Project SGLang through 0.5.21.

**Is there a fix for CVE-2026-109229?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-109229 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-109229?** Check whether you run SGLang Project SGLang at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability exists in NanoNemotronVLImageProcessor, which disables Pillow's Image.MAX_IMAGE_PIXELS protection by setting it to None. Remote attackers can submit small, highly compressed images with extremely large dimensions to the generic image loader, causing uncontrolled memory allocation during decompression. The lack of decompression bomb protection allows worker processes to exhaust available memory, leading to denial of service.

## Affected products

- SGLang Project SGLang through 0.5.21

## Timeline

- 2026-10-12: disclosed

## References

- [https://pypi.org/project/sglang](https://pypi.org/project/sglang)
- [https://github.com/sgl-project/sglang](https://github.com/sgl-project/sglang)

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- [SGLang code injection in _evaluate_filter()](https://junglewise.ai/threats/cve-2026-111391-sglang-0-5-10-through-0-5-22-contains-a-code-injection)