CVE-2026-88831

Busybox: busybox: httpd silently fails open when ip deny rules contain invalid cidr prefix lengths

MEDIUM
5.3
CVSS Score
Published: September 23, 2026 at 05:45 PM UTC
Updated: September 25, 2026 at 11:16 PM UTC
Products not identified yet

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

BusyBox httpd IP deny rules with invalid CIDR prefix lengths fail open, leaving a parsed IP with a zeroed mask so the rule matches no clients.

Affected

We have no canonical product record for this CVE. The source names may not have matched any product.

Remediation

No guide yet

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

References (3)

VDB Entryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/security/cve/CVE-2026-88831
Issue Trackingx_refsource_REDHAT
Source: cverecord
https://bugzilla.redhat.com/show_bug.cgi?id=2531346
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:72111

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

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

CVSS

5.3MEDIUMredhat
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-636

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