Redis unblock client flow use-after-free RCE
CVE-2026-23479 is an authenticated use-after-free vulnerability in Redis affecting redis-server from 7.2.0 through vulnerable releases prior to the vendor fixes. The flaw is in the blocked-client re-execution path, specifically the unblock client flow in src/blocked.c, including unblockClientOnKey(). When Redis re-executes a blocked command, it calls processCommandAndResetClient() but does not correctly handle an error return indicating that the client was freed as a side effect. If the blocked client is evicted during this flow, Redis continues to use the stale client pointer, creating a use-after-free condition. Public reporting states the bug was introduced by the interaction of 2023 changes and remained present across stable branches until the May 2026 fixes. Technical write-ups describe exploitation by reclaiming the freed client allocation with attacker-controlled data so that Redis later processes a fake client structure, which can be leveraged to corrupt memory and ultimately achieve remote code execution.
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Impact, mitigation & remediation
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
Impact
What an attacker gets, and what they’ve been doing with it.
Mitigation
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Remediation
Patch, then assume compromise.
Exploits
No valid public exploits. Mallory filtered out 2 candidates as fakes, detection scripts, or README-only repos.
All candidate exploits were filtered out by Mallory's validation.
Affected products & vendors
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
Recent activity
48 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A critical remote code execution vulnerability in Redis caused by a use-after-free flaw in unblockClientOnKey() within src/blocked.c, affecting versions since 7.2.0 and requiring an authenticated session with specific ACL privileges.
An authenticated remote code execution vulnerability in Redis caused by a use-after-free in blocking-client code, allowing arbitrary OS command execution on the host running Redis.
A use-after-free vulnerability in Redis's unblock client flow that can allow authenticated attackers to achieve remote code execution.
A Redis vulnerability addressed in a Redis security advisory affecting Redis Software and Redis OSS/CE releases across multiple versions.
The version that knows your environment.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.