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CVE Record

CVE-2026-23479: redis-server use-after-free in unblock client flow may allow remote code execution

Redis is an in-memory data structure store. In redis-server from 7.2.0 until 8.6.3, the unblock client flow does not handle an error return from `processCommandAndResetClient` when re-executing a blocked command. If a blocked client is evicted during this flow, an authenticated attacker can trigger a use-after-free that may lead to remote code execution. This has been patched in version 8.6.3.

HighCVSS 7.7Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2026-23479 is a Redis server memory-safety flaw. An authenticated attacker could trigger a use-after-free during blocked-client handling, potentially leading to remote code execution. The issue affects Redis 7.2.0 through versions before 8.6.3 and is fixed in 8.6.3.

Executive priority

Treat as high priority for Redis environments because successful exploitation may allow code execution. Prioritize externally reachable or shared Redis services, then internal instances with broad application access.

Technical view

redis-server mishandles an error return from processCommandAndResetClient while re-executing a blocked command in the unblock client flow. If the blocked client is evicted during that flow, an authenticated attacker can trigger CWE-416 use-after-free with possible code execution impact.

Likely exposure

Exposure is most likely where Redis 7.2.0 to before 8.6.3 is reachable by authenticated users or applications. Internet exposure increases concern, but the source data indicates attacker authentication is required.

Exploitation context

The source bundle does not show CISA KEV listing or confirmed active exploitation. CVSS 4.0 rates this 7.7 high, with network attack vector, low privileges required, no user interaction, and high attack complexity.

Researcher notes

Focus validation on version range, authentication exposure, and blocked-client code paths. Do not assume exploit availability from the provided sources. The most defensible remediation is upgrading to the fixed upstream or vendor package.

Mitigation direction

  • Upgrade Redis to 8.6.3 or a vendor-supported fixed package.
  • Apply relevant Red Hat advisories where Redis is distro-managed.
  • Restrict Redis network access to trusted application paths.
  • Review Redis authentication and ACL scope for least privilege.
  • Check vendor guidance for any environment-specific mitigations.

Validation and detection

  • Inventory Redis server versions across production and staging.
  • Flag redis-server versions >=7.2.0 and <8.6.3.
  • Confirm patched packages from upstream Redis or Red Hat advisories.
  • Review exposure paths for authenticated Redis access.
  • Verify monitoring for Redis crashes or abnormal restarts.
Prepared
Confidence
high
Sources
12

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-2026-23479 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
7.7 (4.0)
Known Exploited
No
Published

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

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
7.7CVSS 4.0HighCVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——GitHub_M
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H1.65.9redhat-SADP

Vulnerability scoring details

Base CVSS 4.0 score

7.7High
CVSS 4.0 vector shape for CVE-2026-23479Attack 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:H/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: use-after-free in unblock client flow may allow remote code execution
other:Red Hat severity ratingcvssV3_1
  • 2026-05-05T17:01:54.051Z: Reported to Red Hat.
  • 2026-05-05T16:36:05.486Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
redisredis>= 7.2.0, < 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