PT-2025-23226 · Vllm · Vllm

Derekhiggins · Published 2025-04-27 · Updated 2025-06-24 · CVE-2025-48942

Positive Technologies (AI Summary)

CVSS v2.0

6.8

Medium

Base vector

AV:N/AC:L/Au:S/C:N/I:N/A:C

Name of the Vulnerable Software and Affected Versions vLLM versions 0.8.0 through 0.9.0

Description The issue arises when the /v1/completions API endpoint is hit with an invalid json schema as a Guided Param, causing the vLLM server to crash. This is similar to a previously known issue but concerns regex instead of a JSON schema. The problem is triggered by an invalid json schema in the guided json parameter of the API call. For example, using {"properties":{"reason":{"type": "stsring"}}} as the guided json will provoke an error. The estimated number of potentially affected devices is not provided.

Technical details about exploitation include:

• API Endpoint: /v1/completions
• Vulnerable Parameter: guided json
• The error occurs because the json schema provided in the guided json parameter is invalid, specifically due to a typo in the type definition ("stsring" instead of "string").

Recommendations For versions 0.8.0 through 0.9.0, update to version 0.9.0 or later to fix the issue. As a temporary workaround, consider validating the json schema in the guided json parameter before passing it to the /v1/completions API endpoint to prevent the server from crashing. Restrict access to the /v1/completions API endpoint until the update can be applied.

Exploit

Fix

DoS

Weakness Enumeration

CWE-248

Related Identifiers

BDU:2025-11321

CVE-2025-48942

GHSA-6QC9-V4R8-22XG

PYSEC-2025-54

Affected Products

Vllm

References · 18

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/48xxx/CVE-2025-48942.json · Exploit
• https://github.com/vllm-project/vllm/commit/08bf7840780980c7568c573c70a6a8db94fd45ff · Patch
• https://github.com/vllm-project/vllm/pull/17623 · Patch
• https://github.com/vllm-project/vllm/security/advisories/GHSA-6qc9-v4r8-22xg · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-6qc9-v4r8-22xg · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2025-48942 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-48942 · Security Note
• https://bdu.fstec.ru/vul/2025-11321 · Security Note
• https://osv.dev/vulnerability/PYSEC-2025-54 · Vendor Advisory
• https://github.com/vllm-project/vllm · Note
• https://github.com/vllm-project/vllm/issues/17248 · Note
• https://github.com/pypa/advisory-database/tree/main/vulns/vllm/PYSEC-2025-54.yaml · Note
• https://t.me/cvenotify/126568 · Telegram Post
• https://t.me/cvetracker/25037 · Telegram Post
• https://twitter.com/VulmonFeeds/status/1928559240697749568 · Twitter Post