CVE-2026-9540: vllm-project vllm OpenAI-compatible Serving Path denial of service
Vulnerability summary
CVE-2026-9540 is a medium (CVSS 6.9) Improper Resource Shutdown or Release vulnerability in vllm-project vllm. EPSS estimates a 0.72% chance of exploitation in the next 30 days, higher than 53.5% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 26-05-2026PublishedVulnerability first disclosed.
- 26-05-2026Last modifiedVulnerability information updated.
Description
A vulnerability was identified in vllm-project vllm 0.19.0. This issue affects some unknown processing of the component OpenAI-compatible Serving Path. Such manipulation leads to denial of service. It is possible to launch the attack remotely. The exploit is publicly available and might be used. The pull request to fix this issue awaits acceptance.
CVSS metrics
10 scores · 4 sources · 4 versions- OSV · PypiEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
- OSV · ChainguardEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
- NVDNIST5.5MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XDiffers
- OSV · PypiEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- NVDNIST5.0MediumAV:N/AC:L/Au:N/C:N/I:N/A:P
EPSS trend
Probability
0.72%
Chance of exploitation in the next 30 days
Percentile
54%
Versus all other CVEs
30-day change
Increase +0.30 pp
From 0.43% on 22-09-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
1 foundVllm
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Chainguard3 products
- py3.10-vllm-cuda-12.4All versions (No fix recorded)
- py3.12-vllm-cuda-12.4All versions (No fix recorded)
- tritonserver-backend-vllm-cuda-12.9All versions (No fix recorded)
PyPI1 product
- vllm≤ 0.19.0
Vllm-project1 product
- vllm0.19.0
3 vendors · 5 products
References
13 links
- github.com/vllm-project/vllmPACKAGE
Show all 13 references
- pypi.org/project/vllmPACKAGE