CVE-2026-88834

Busybox: busybox: httpd user existence oracle in non-default shadow-disabled builds

Published Oct 13, 2026 CVSS 3.1 · 3.7 Low EPSS < 1% KEV · Not listed
Description
A flaw was found in BusyBox's httpd web server. When configured with system password authentication, a user existence oracle may exist in certain build configurations. An attacker could distinguish existing from non-existing usernames by observing authentication failure behavior. Impact is limited to username enumeration and requires non-default compile options or uncommon password file states; default BusyBox builds with shadow password support are not affected.

Remediation

Vendor Workaround

Prefer explicit username:password entries in httpd.conf instead of /:*:* system-password wildcards. Use PAM-based authentication where available. Ensure BusyBox is built with FEATURE_SHADOWPASSWDS enabled (default).

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Busybox
Busybox busybox
Vendors & Products Busybox
Busybox busybox
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description A flaw was found in BusyBox's httpd web server. When configured with system password authentication, a user existence oracle may exist in certain build configurations. An attacker could distinguish existing from non-existing usernames by observing authentication failure behavior. Impact is limited to username enumeration and requires non-default compile options or uncommon password file states; default BusyBox builds with shadow password support are not affected.
Title Busybox: busybox: httpd user existence oracle in non-default shadow-disabled builds
First Time appeared Redhat
Redhat hummingbird
Weaknesses CWE-203
CPEs cpe:/a:redhat:hummingbird:1
Vendors & Products Redhat
Redhat hummingbird
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Oct 13, 2026, 5:16 PM
Reserved
Sep 10, 2026, 9:42 AM
Status
Awaiting Analysis
Published
Oct 13, 2026, 5:17 PM
Modified
Oct 15, 2026, 4:33 PM
Severity
Low
Public date
Oct 13, 2026, 1:49 PM