CVE-2026-86463

Apache CXF: FIQL Query Parser Denial of Service

HIGH
7.5
CVSS Score
Published: October 9, 2026 at 10:18 AM UTC
Updated: October 20, 2026 at 12:41 PM UTC
1 product affected across 1 vendorCXF

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Severity
HIGH7.5
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

Description

Apache CXF's FIQL query parser has a vulnerability in how it searches for operators in query expressions. The search pattern can get stuck trying many combinations when it encounters a long string without an operator, causing the parser to consume excessive CPU time. An attacker can send a crafted query to make the server use up CPU resources, potentially slowing down or stopping other requests. The fix was to limit FIQL expressions to 4 KiB by default, preventing attackers from sending extremely long inputs while still allowing normal queries. Users are recommended to upgrade to versions 4.2.4 or 4.1.9 or 3.6.13, which fix this issue.

Affected

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

95%
v < 3.6.134.0.0 ≤ v < 4.1.94.2.0 ≤ v < 4.2.44.0.04.2.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

Vendor AdvisoryIssue Tracking
Source: cverecord
https://lists.apache.org/thread.html/mv5qfmd27gkbvt3k6by9db5bolrsbgy1
Mailing ListThird Party Advisory
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2026/10/09/8

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

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

CVSS

7.5HIGHCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-400

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