Description
A vulnerability was found in vLLM up to 0.19.0. The affected element is the function has_mamba_layers of the file vllm/v1/kv_cache_interface.py of the component KV Block Handler. Performing a manipulation results in uninitialized resource. It is possible to initiate the attack remotely. The attack is considered to have high complexity. The exploitability is described as difficult. The exploit has been made public and could be used. The existence of this vulnerability is still disputed at present. The proposed patch did not fix the issue. A 3rd party explains: "The divergence could be explained by a benign and expected vLLM behavior where vLLM server could group concurrent requests together resulting in different input shapes based on varying request arrival time. The differences in grouped input shapes could call different kernels with could produce difference results due to rounding and differences in order of operations. There is an environment variable VLLM_BATCH_INVARIANT=1 for users that desire to have deterministic output with temperature 0.0."
Published: 2026-04-27
Score: 6.3 Medium
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories
Source ID Title
Github GHSA Github GHSA GHSA-x368-4g9h-fvv4 vLLM makes Use of Uninitialized Resource
History

Tue, 25 Aug 2026 19:30:00 +0000

Type Values Removed Values Added
Description A vulnerability was found in vllm up to 0.19.0. The affected element is the function has_mamba_layers of the file vllm/v1/kv_cache_interface.py of the component KV Block Handler. Performing a manipulation results in uninitialized resource. It is possible to initiate the attack remotely. The attack is considered to have high complexity. The exploitability is described as difficult. The exploit has been made public and could be used. The patch is named 1ad67864c0c20f167929e64c875f5c28e1aad9fd. To fix this issue, it is recommended to deploy a patch. A vulnerability was found in vLLM up to 0.19.0. The affected element is the function has_mamba_layers of the file vllm/v1/kv_cache_interface.py of the component KV Block Handler. Performing a manipulation results in uninitialized resource. It is possible to initiate the attack remotely. The attack is considered to have high complexity. The exploitability is described as difficult. The exploit has been made public and could be used. The existence of this vulnerability is still disputed at present. The proposed patch did not fix the issue. A 3rd party explains: "The divergence could be explained by a benign and expected vLLM behavior where vLLM server could group concurrent requests together resulting in different input shapes based on varying request arrival time. The differences in grouped input shapes could call different kernels with could produce difference results due to rounding and differences in order of operations. There is an environment variable VLLM_BATCH_INVARIANT=1 for users that desire to have deterministic output with temperature 0.0."
Title vllm KV Block kv_cache_interface.py has_mamba_layers uninitialized resource vLLM KV Block kv_cache_interface.py has_mamba_layers uninitialized resource
References
Metrics cvssV2_0

{'score': 5.1, 'vector': 'AV:N/AC:H/Au:N/C:P/I:P/A:P/E:POC/RL:OF/RC:C'}

cvssV3_0

{'score': 5.6, 'vector': 'CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C'}

cvssV3_1

{'score': 5.6, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C'}

 cvssV2_0

{'score': 5.1, 'vector': 'AV:N/AC:H/Au:N/C:P/I:P/A:P/E:POC/RL:U/RC:UR'}

cvssV3_0

{'score': 5.6, 'vector': 'CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:R'}

cvssV3_1

{'score': 5.6, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:R'}

Tue, 28 Apr 2026 12:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 threat_severity

Moderate

Mon, 27 Apr 2026 18:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Mon, 27 Apr 2026 17:15:00 +0000

Type Values Removed Values Added
Description A vulnerability was found in vllm up to 0.19.0. The affected element is the function has_mamba_layers of the file vllm/v1/kv_cache_interface.py of the component KV Block Handler. Performing a manipulation results in uninitialized resource. It is possible to initiate the attack remotely. The attack is considered to have high complexity. The exploitability is described as difficult. The exploit has been made public and could be used. The patch is named 1ad67864c0c20f167929e64c875f5c28e1aad9fd. To fix this issue, it is recommended to deploy a patch.
Title vllm KV Block kv_cache_interface.py has_mamba_layers uninitialized resource
First Time appeared Vllm
Vllm vllm
Weaknesses CWE-908
CPEs cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*
Vendors & Products Vllm
Vllm vllm
References
Metrics cvssV2_0

{'score': 5.1, 'vector': 'AV:N/AC:H/Au:N/C:P/I:P/A:P/E:POC/RL:OF/RC:C'}

cvssV3_0

{'score': 5.6, 'vector': 'CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C'}

cvssV3_1

{'score': 5.6, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C'}

cvssV4_0

{'score': 6.3, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P'}

Subscriptions

Vllm Vllm
cve-icon MITRE

Status: PUBLISHED

Assigner: VulDB

Published:

Updated: 2026-08-25T19:07:56.947Z

Reserved: 2026-04-26T19:38:00.529Z

Link: CVE-2026-7141

cve-icon Vulnrichment

Updated: 2026-04-27T17:41:14.509Z

cve-icon NVD

Status : Modified

Published: 2026-04-27T17:16:45.637

Modified: 2026-08-25T20:17:08.387

Link: CVE-2026-7141

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-04-27T16:45:12Z

Links: CVE-2026-7141 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-08-26T06:45:03Z

Weaknesses