CVE-2026-88831 (GCVE-0-2026-88831)

Vulnerability from cvelistv5 – Published: 2026-09-23 17:45 – Updated: 2026-09-25 22:28
VLAI
Title
Busybox: busybox: httpd silently fails open when ip deny rules contain invalid cidr prefix lengths
Summary
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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-23 18:08 UTC
CWE
  • CWE-636 - Not Failing Securely ('Failing Open')
Assigner
References
URL Tags
https://access.redhat.com/errata/RHSA-2026:72111 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-88831 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2531346 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat Hardened Images Unaffected: 1.37.0-9.1.hum1 , < * (rpm)
    cpe:/a:redhat:hummingbird:1
Create a notification for this product.
Date Public
2026-09-23 16:35
Credits
Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue.
Show details on NVD website
To clipboard 

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