CVE-2026-10813: LMCache 16-bit Multimodal Hash Collision Can Vulnerability

LOW
Advisory Identifier: GHSA-3hh9-752g-5g22
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CVSS 3.6
CWE-327
Published
Advisory Summary

CVE-2026-10813 is a LOW (CVSS 3.6) 16-bit multimodal hash collision can vulnerability (CWE-327: Use of a Broken or Risky Cryptographic Algorithm) affecting LMCache libraries in the PyPI ecosystem. The issue involves 16-bit multimodal hash collision can poison kv cache entries. Remediation is available in the latest vendor maintenance releases.

CVE-2026-10813 at a Glance

CVE Identifier CVE-2026-10813
GHSA Identifier GHSA-3hh9-752g-5g22
Severity LOW
CVSS v3.1 Base Score 3.6
CWE Classification CWE-327: Use of a Broken or Risky Cryptographic Algorithm
Affected Product LMCache
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 3.6

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L).

Attack Vector Local (AV:L)
Attack Complexity High (AC:H)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2026-10813

To remediate this vulnerability, upgrade all affected LMCache dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

lmcache fixed: Latest secure release 
pip install lmcache>=Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show lmcache

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-10813, inspect your installed packages using pip:

pip show lmcache

Analyze the terminal output to locate any version of LMCache in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The pip show lmcache command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-327: Use of a Broken or Risky Cryptographic Algorithm, where the product uses a broken or risky cryptographic algorithm or protocol. In LMCache, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

A flaw has been found in LMCache up to 0.4.6. This affects the function hex_hash_to_int16 of the file lmcache/integration/vllm/utils.py of the component KV Cache Handler. Executing a manipulation can lead to use of weak hash. The attack needs to be launched locally. The attack requires a high level of complexity. It is indicated that the exploitability is difficult. The exploit has been published and may be used. The pull request to fix this issue awaits acceptance.

CVE-2026-10813 Affected LMCache Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
lmcache
pypi/lmcache
PyPI
≤ 0.4.6

References

NVD — CVE-2026-10813 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-10813
LMCache Source Repository REPOSITORY
https://github.com/LMCache/LMCache/issues/3301
LMCache Source Repository REPOSITORY
https://github.com/LMCache/LMCache/pull/2932
LMCache Source Repository REPOSITORY
https://github.com/LMCache/LMCache
vuldb.com/cve/cve-2026-10813 WEB
https://vuldb.com/cve/CVE-2026-10813
vuldb.com/submit/831641 WEB
https://vuldb.com/submit/831641
vuldb.com/vuln/368261 WEB
https://vuldb.com/vuln/368261
vuldb.com/vuln/368261/cti WEB
https://vuldb.com/vuln/368261/cti

Frequently Asked Questions

What is CVE-2026-10813?
CVE-2026-10813 is a security vulnerability in LMCache involving 16-bit multimodal hash collision can poison KV cache entries under CWE-327: Use of a Broken or Risky Cryptographic Algorithm.
Which LMCache versions are affected?
Affected versions include releases prior to current release patches across affected packages: lmcache.
What version fixes CVE-2026-10813?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is lmcache affected?
Yes, lmcache is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2026-10813?
CVE-2026-10813 has a CVSS v3.1 base score of 3.6 (LOW) with vector string CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L.
What CWE is associated with CVE-2026-10813?
CVE-2026-10813 is classified under CWE-327: Use of a Broken or Risky Cryptographic Algorithm (The product uses a broken or risky cryptographic algorithm or protocol.).
How can I check PyPI dependencies for CVE-2026-10813?
Run the dependency tree command: 'pip show lmcache'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-3hh9-752g-5g22",
  "modified" : "2026-07-15T22:10:24Z",
  "published" : "2026-06-04T18:30:31Z",
  "aliases" : [ "CVE-2026-10813" ],
  "summary" : "LMCache: 16-bit multimodal hash collision can poison KV cache entries",
  "details" : "A flaw has been found in LMCache up to 0.4.6. This affects the function hex_hash_to_int16 of the file lmcache/integration/vllm/utils.py of the component KV Cache Handler. Executing a manipulation can lead to use of weak hash. The attack needs to be launched locally. The attack requires a high level of complexity. It is indicated that the exploitability is difficult. The exploit has been published and may be used. The pull request to fix this issue awaits acceptance.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:P"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "lmcache"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.4.6"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-10813"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/LMCache/LMCache/issues/3301"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/LMCache/LMCache/pull/2932"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/LMCache/LMCache"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/cve/CVE-2026-10813"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/submit/831641"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/vuln/368261"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/vuln/368261/cti"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-327" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-15T22:10:24Z",
    "nvd_published_at" : "2026-06-04T16:16:32Z"
  }
}