Vulnerability · Published Oct 13, 2026 · Assigned by redhat

CVE-2026-88834Busybox: busybox: httpd user existence oracle in non-default shadow-disabled builds

Low 3.7

In plain English

A low-severity security flaw in Red Hat Hardened Images from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).

Severity (CVSS 3.1)3.7Low

Exploit odds (30 days)0.2%top 87.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	busybox	no fix listed	DEBIAN-CVE-2026-88834
Debian:13	busybox	no fix listed	DEBIAN-CVE-2026-88834
Debian:14	busybox	no fix listed	DEBIAN-CVE-2026-88834
Ubuntu:22.04:LTS	busybox	no fix listed	UBUNTU-CVE-2026-88834
Ubuntu:24.04:LTS	busybox	no fix listed	UBUNTU-CVE-2026-88834
Ubuntu:26.04:LTS	busybox	no fix listed	UBUNTU-CVE-2026-88834
Ubuntu:26.10	busybox	no fix listed	UBUNTU-CVE-2026-88834

Affected products (as reported)

Vendor	Product	Versions
Red Hat	Red Hat Hardened Images	see references

Weakness: CWE-203 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

References

https://access.redhat.com/security/cve/CVE-2026-88834 vdb-entry, x_refsource_REDHAT
RHBZ#2531348 issue-tracking, x_refsource_REDHAT