CVE-2025-46818

MEDIUMNuclei

Redis: Authenticated users can execute LUA scripts as a different user

Title source: CVE List
Search associated code STIX 2.1 vulnerability STIX 2.1 with PoCs

Record summary

CVE-2025-46818 has a selected CVSS score of 6.0 (medium); EIP currently links 1 repository PoC and 1 Nuclei template.

Description

Redis is an open source, in-memory database that persists on disk. Versions 8.2.1 and below allow an authenticated user to use a specially crafted Lua script to manipulate different LUA objects and potentially run their own code in the context of another user. The problem exists in all versions of Redis with LUA scripting. This issue is fixed in version 8.2.2. A workaround to mitigate the problem without patching the redis-server executable is to prevent users from executing LUA scripts. This can be done using ACL to block a script by restricting both the EVAL and FUNCTION command families.

Description source: CVE List

Exploitation context

Available material

Repository PoCs
1
Nuclei templates
1

CISA SSVC decision

ExploitationNone
AutomatableNo
Technical impactTotal

CISA Coordinator · SSVC 2.0.3 · Evaluated Oct 3, 2025 · Source: CVE List

Affected products and versions

1
ProductSourceVersion range

redis

Browse redis / redis
CVE List< 8.2.2affected

Proofs of concept

1

Repository PoCs

GitHubdwisiswant0/CVE-2025-46818Repository PoCby dwisiswant00Scanner2 files

2.9 KiB

GitHub
PoC details
Analysisdeepseek-v4-pro:cloud ·

Technical assessment

The artifact is a Lua script and README that checks for the presence of deprecated Lua APIs (getfenv, setfenv, newproxy) and attempts to modify the string metatable to inject a helper method. It reports on the availability of these APIs and the success of the metatable modification, functioning as a vulnerability scanner rather than a full exploit.

Backdoor review

No backdoor observed in reviewed code

The repository contains a proof-of-concept Lua script and README for CVE-2025-46818. The script demonstrates the claimed vulnerability by checking for deprecated Lua APIs and modifying the string metatable to inject an 'escalate' method that calls redis.pcall('ACL', 'WHOAMI'). This behavior is consistent with the described Redis sandbox escape and does not exhibit any concealed backdoor, credential theft, persistence, or unrelated payload. The script's actions are fully disclosed in the accompanying README.

ClassificationScanner
Model confidence95%
AuthenticationRequired
Languagesluamarkdown
Target softwareredis
Attack typescode injectionprivilege escalation
Evidence & reasoningClassification basis · observed behavior · safety review
Technical evidence

Classification basis and observed behavior

Classification basis

The Lua script primarily checks for the presence of vulnerable conditions (deprecated APIs, mutable metatables) and reports on them. It does not autonomously exploit the vulnerability to achieve code execution in another user's context; it only injects a helper and requires a separate, manual step to invoke it. The README describes it as a 'repro' and verification script, consistent with a scanner.

CVE-2025-46818.lua:1CVE-2025-46818.lua:6-8README.md:17

Requirements

  • Authenticated access to a Redis instance with Lua scripting enabled.README.md:2
  • Redis version vulnerable to CVE-2025-46818 (e.g., 8.2.1).README.md:11

Observed behavior

  • Checks if deprecated Lua functions getfenv, setfenv, and newproxy are available.CVE-2025-46818.lua:6-8
  • Attempts to modify the string metatable to inject an 'escalate' method that calls redis.pcall('ACL', 'WHOAMI').CVE-2025-46818.lua:19-31
  • Returns a report indicating the availability of deprecated APIs and whether the metatable was patched.CVE-2025-46818.lua:10-14CVE-2025-46818.lua:39
Safety-review evidence

Behaviors behind the backdoor verdict

Observables

Lua Script Behavior
Payload withheldDemonstrates the claimed vulnerability by injecting a method that executes a privileged Redis command, matching the CVE description of running code in another user's context.CVE-2025-46818.lua:24-31
Deprecated Api Check
Payload withheldVerifies the presence of deprecated Lua APIs that are part of the vulnerability, as described in the CVE and README.CVE-2025-46818.lua:6-8
Review boundaries

What the analysis did not establish

  • The evidence does not include execution output or confirmation that the script successfully ran against a live Redis instance.
  • The script's metatable injection is a partial step; full exploitation requires a separate privileged script execution, which is not automated in the provided code.
  • Only the two text files (CVE-2025-46818.lua and README.md) were provided and reviewed; no other files exist in the repository snapshot.
  • The review does not assess whether the PoC actually works as claimed or is safe to execute in any environment.
Model interpretation

This review is limited to the supplied PoC code and context. It does not assert that the code works or is safe to execute.

Nuclei templates

1
ProjectDiscoveryHIGHRedis Lua Sandbox < 8.2.2 - Cross-User Escape

Redis is an open source, in-memory database that persists on disk. Versions 8.2.1 and below allow an authenticated user to use a specially crafted Lua script to manipulate different LUA objects and potentially run their own code in the context of another user. The problem exists in all versions of Redis with LUA scripting. This issue is fixed in version 8.2.2. A workaround to mitigate the problem without patching the redis-server executable is to prevent users from executing LUA scripts. This can be done using ACL to block a script by restricting both the EVAL and FUNCTION command families.

Impact

Authenticated users can execute arbitrary code in the context of other users, potentially leading to full system compromise.

Remediation

Upgrade to version 8.2.2 or later.

Authorspussycat0x
Template tagscvecve2025jsredisnetworkpassiveauthenticatedvuln
Shodan: product:"redis"
https://github.com/dwisiswant0/CVE-2025-46818

Source: ProjectDiscovery

References

3