CVE-2026-88831
📛 CVE Title
Busybox: busybox: httpd silently fails open when ip deny rules contain invalid cidr prefix lengths
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- redhat
- CVSS severity
- MEDIUM
- CVSS score
- 5.3 / 10
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N- Effective score
- 5.3 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-636 - Reserved
- 2026-09-10
- Published
- 2026-09-23 17:45 UTC
- Last updated
- 2026-09-23 18:11 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/88xxx/CVE-2026-88831.json
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-23 18:17:10 UTC
- NVD last modified
- 2026-09-23 19:19:42 UTC
- NVD CVSS v3.1
- 5.3 / 10 MEDIUM source: secalert@redhat.com
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 1.4 / 10
NVD / KEV / EPSS data refreshed 2026-09-24 04:32 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-85509 - Assigner
- redhat
- Published
- Sep 23, 2026, 5:45:23 PM
- Updated
- Sep 23, 2026, 6:11:48 PM
- EUVD base score (CVSS 3.1)
-
5.3 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - EUVD-reported EPSS
- 0.0000
- Aliases
-
GHSA-w27x-jw4w-69xf
ENISA 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 products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Red Hat | Red Hat Hardened Images | — | — |
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
- https://access.redhat.com/security/cve/CVE-2026-88831 vdb-entryx_refsource_REDHAT
- RHBZ#2531346 issue-trackingx_refsource_REDHAT
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://access.redhat.com/security/cve/CVE-2026-88831 secalert@redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2531346 secalert@redhat.com
Remediations (10)
-
web:cvetodo.com
CVE-2026-88831 is a CVSS 5.3 medium-severity vulnerability in Red Hat products. Full technical analysis, mitigations , and exploit status — updated in real time.
2026-09-24 11:48 UTC -
web:isitpatched.com
CVE - 2026 -68831: MEDIUM severity (CVSS 5.5). Affected products, impact, and what to do.
2026-09-24 11:48 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-09-24 11:48 UTC -
web:support.microsoft.com
Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...
2026-09-24 11:48 UTC -
web:support.servicenow.com
Due to additional analysis provided by the security researcher who discovered CVE - 2026 -6876, we have upgraded the severity rating of CVE - 2026 -6876 from High to Critical. This change affects only the severity
2026-09-24 11:48 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-09-24 11:48 UTC -
web:www.fedramp.gov
Ruleset Reference 20x 20x Class C Boundary Rulesets Vulnerability Detection and Response The Vulnerability Detection and Response rules require providers to continuously identify, analyze, prioritize, mitigate, and remediate vulnerabilities and related exposures through automated systems. These rules give providers flexibility in implementation while ensuring agencies receive the information ...
2026-09-24 11:48 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-24 11:48 UTC -
web:www.veeam.com
When a vulnerability is identified, our team promptly develops a patch to address and mitigate the risk. In line with our dedication to transparency, we publicly disclose the vulnerability and provide detailed mitigation information.
2026-09-24 11:48 UTC -
web:www.youtube.com
hihihihihihihiThis song is also known as "I can't fix you mashup remix"this got a lot of views on tiktok so imma upload it herecan't put links since this is ...
2026-09-24 11:48 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-88831.json.
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