Decompression amplification in SGLang load_audio exhausts memory
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
Versions of SGLang through 0.5.21 contain a flaw in load_audio, which decodes compressed audio without duration or sample limits (CWE-409). A remote attacker without authentication submits small FLAC-encoded silence files through audio_url or audio_data inputs that expand into massive PCM buffers, exhausting worker memory and CPU for denial of service.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
SGLang through 0.5.21 contains a decompression amplification vulnerability in load_audio that allows remote attackers to exhaust memory by submitting highly compressed audio decoded without duration or sample limits. Attackers can supply small FLAC-encoded silence files through audio_url or audio_data inputs that expand into massive PCM buffers, exhausting worker memory and CPU for denial of service.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| sgl-project | sglang | up to 0.5.21 | — | No fix listed | CNA |
- sglang Vendorsgl-project Affected up to 0.5.21 Fixed in — No fix listed CNA
Remediation
The sources list no fixed version for SGLang.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Timeline
- 2026-10-12 Threatist record created from CVE-2026-109226
- 2026-10-12 Alias added: GHSA-h3xf-3226-h48g
- 2026-10-13 Priority changed: MEDIUM → LOW
- 2026-10-13 CISA SSVC decision points changed
- 2026-10-13 Priority changed: LOW → HIGH
References
Other 6
- GitHub Issue #43708
- https://github.com/sgl-project/sglang/blob/v0.5.21/python/sglang/srt/utils/common.py#L1783
- https://github.com/sgl-project/sglang/blob/v0.5.21/python/sglang/srt/utils/common.py#L1801-L1803
- https://github.com/sgl-project/sglang/blob/v0.5.21/python/sglang/srt/multimodal/audio_from_video.py#L128
- https://github.com/sgl-project/sglang/blob/v0.5.21/python/sglang/srt/multimodal/processors/base_processor.py#L996
- https://github.com/sgl-project/sglang
More sgl-project vulnerabilities
- TI-2026-76247 Denial of service in SGLang expert-distribution recording endpoint CVSS 4.0HIGH 8.7
- TI-2026-70996 SGLang disables decompression bomb check, enabling denial of service CVSS 4.0HIGH 8.7
- TI-2026-70994 SGLang Memory Exhaustion DoS via Qwen-VL Video Preprocessing CVSS 4.0HIGH 8.7
- TI-2026-65453 SGLang through 0.5.20 Denial of Service via Duplicate bootstrap_room CVSS 4.0HIGH 8.7
- TI-2026-75290 Code injection in SGLang debug dumper filter CVSS 4.0CRITICAL 9.2
- TI-2026-76467 Server-side request forgery in SGLang via bootstrap_host and bootstrap_port CVSS 4.0MEDIUM 6.9
Sources
- CVE-2026-109226 · CVE Program
- CVE-2026-109226 · NVD
- FIRST EPSS
- GHSA-h3xf-3226-h48g · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences