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TI-2026-22005 Aliases CVE-2026-27623

Valkey has Pre-Authentication DOS from malformed RESP request

Priority LOW 39CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Valkey is a distributed key-value database. Starting in version 9.0.0 and prior to version 9.0.3, a malicious actor with network access to Valkey can cause the system to abort by triggering an assertion. When processing incoming requests, the Valkey system does not properly reset the networking state after processing an empty request. A malicious actor can then send a request that the server incorrectly identifies as breaking server side invariants, which results in the server shutting down. Version 9.0.3 fixes the issue. As an additional mitigation, properly isolate Valkey deployments so that only trusted users have access.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00405 35th percentileScored 2026-11-07
Fix Fixed valkey (valkey-io): 9.0.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MLflowvalkey9.0.0 to before 9.0.39.0.3Patch availableCNA
  • valkey VendorMLflow Affected 9.0.0 to before 9.0.3 Fixed in 9.0.3 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:lfprojects:valkey:*:*:*:*:*:*:*:*9.0.0 to before 9.0.3VulnerableMLflow
  • cpe:2.3:a:lfprojects:valkey:*:*:*:*:*:*:*:* Versions 9.0.0 to before 9.0.3 Vulnerable ·MLflow

Remediation

  • Fix · CNA valkey (valkey-io) Fixed in 9.0.3

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

Not affected: 2 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-27623
  2. 2026-10-12 EPSS moved to the 50th–90th percentile
  3. 2026-10-25 EPSS moved to the below the 50th percentile
  4. 2026-10-25 Priority changed: MEDIUM → LOW

References

Advisory 1

  • TI-2025-31759 Redis Lua Use-After-Free may lead to remote code execution CVSS 3.1CRITICAL 10.0
  • TI-2026-17565 Malformed Valkey Cluster bus message can lead to Remote DoS CVSS 3.1HIGH 7.5
  • TI-2025-15565 Redis DoS Vulnerability due to unlimited growth of output buffers abused by unauthenticated client CVSS 3.1HIGH 7.5
  • TI-2025-41429 Valkey Affected by RESP Protocol Injection via Lua error_reply CVSS 3.1HIGH 8.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences