CVE-2026-53935

CiliumLocalRedirectPolicy addressMatcher allows cross-namespace service traffic hijacking and can break service translation

MEDIUM
6.9
CVSS Score
Published: July 7, 2026 at 08:44 PM UTC
Updated: July 10, 2026 at 06:08 PM UTC
1 product affected across 1 vendorCilium

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Severity
MEDIUM6.9
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

Cilium is a networking, observability, and security solution. Prior to 1.17.16, from 1.18.2 to 1.18.9, and from 1.19.0 to 1.19.3, users with the ability to create CiliumLocalRedirectPolicies can specify arbitrary ClusterIPs via addressMatcher, enabling hijacking traffic to Services in any namespace and bypassing namespace scoping enforced by serviceMatcher; deleting such a policy can also corrupt Cilium internal service state and stop service translation for the affected Service. This issue is fixed in versions 1.17.16, 1.18.10, and 1.19.4.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.17.16v < 1.18.10v < 1.19.4
Affected range stops below 1.17.16, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.18.10, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.19.4, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.9MEDIUMGitHub_M
Attack Vector
ADJACENT_NETWORK
Complexity
LOW
Privileges
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality
LOW
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-863

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