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CVE Record

CVE-2026-23631: redis-server Lua use-after-free may allow remote code execution

Redis is an in-memory data structure store. In all versions of redis-server with Lua scripting, an authenticated attacker can exploit the master-replica synchronization mechanism to trigger a use-after-free on replicas where replica-read-only is disabled or can be disabled, which may lead to remote code execution. A workaround is to prevent users from executing Lua scripts or avoid using replicas where replica-read-only is disabled. This is patched in version 8.6.3.

HighCVSS 8.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

Redis servers before 8.6.3 can be exposed to a serious memory-safety flaw when Lua scripting and replica synchronization are in play. An authenticated attacker could potentially execute code on affected replicas if replica read-only protections are disabled or can be disabled.

Executive priority

Treat as a near-term remediation item for production Redis, especially customer-facing, shared, or replicated environments. Patch or restrict risky Lua and replica configurations promptly, but do not claim emergency exploitation without new evidence.

Technical view

CVE-2026-23631 is a CWE-416 use-after-free in redis-server Lua scripting. The described trigger involves master-replica synchronization and replicas where replica-read-only is disabled or disableable. CVSS is 8.8 with low attack complexity, network access, and low privileges required. Redis says 8.6.3 patches it.

Likely exposure

Exposure is most likely in Redis deployments below 8.6.3 that allow authenticated users to run Lua scripts and use replicas without enforced read-only mode. Internet exposure, shared Redis access, or weak Redis authentication materially increases urgency.

Exploitation context

The supplied sources do not show CISA KEV listing or confirmed active exploitation. The issue is still high risk because the vendor describes possible remote code execution by an authenticated attacker under specific replica and Lua conditions.

Researcher notes

Key constraints are authentication, Lua scripting, and replica read-only state. Validate exposure through configuration and version review rather than proof-of-concept testing. The supplied bundle does not include exploit availability, detailed affected build matrix, or non-Redis product impact.

Mitigation direction

  • Upgrade Redis to version 8.6.3 or later.
  • Apply relevant Red Hat errata for packaged Redis deployments.
  • Prevent untrusted users from executing Lua scripts.
  • Avoid replicas where replica-read-only is disabled or disableable.
  • Review Redis and OS vendor guidance for environment-specific fixes.

Validation and detection

  • Inventory Redis servers and confirm versions are below or at 8.6.3.
  • Identify deployments using Redis Lua scripting.
  • Check whether replicas enforce replica-read-only.
  • Review Redis ACLs for users allowed to run Lua scripts.
  • Confirm vendor patches are installed across images and hosts.
  • Prioritize externally reachable or multi-tenant Redis instances.
Prepared
Confidence
high
Sources
8

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-416: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

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description · low confidence lookup

Execution behavior lookup

The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2026-23631 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
8.8 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
5Timeline events
2ADP providers
13Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: total

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
8.8CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H2.85.9redhat-SADP
6.1CVSS 4.0MediumCVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N——GitHub_M

Vulnerability scoring details

Base CVSS 4.0 score

6.1Medium
CVSS 4.0 vector shape for CVE-2026-23631Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. ADP timelineredhat-SADP

    Made public.

  3. CVE publishedCVE Program

    The CVE record was published.

  4. ADP timelineredhat-SADP

    Reported to Red Hat.

  5. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
redhat-SADPredis: Remote code execution via use-after-free in Lua scripting
other:Red Hat severity ratingcvssV3_1
  • 2026-05-05T17:02:23.286Z: Reported to Red Hat.
  • 2026-05-05T16:39:32.337Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
redisredis< 8.6.3Listed
Weakness

CWE details

CWE-416

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-416 · source CWE mapping

Use After Free

Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs