CVE-2026-88834 (CVSS 3.7)

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.

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CVSS v3.1 Score

3.7

LOW

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS — Exploit Prediction

0.0022

Probability of exploitation

0.12%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-203 CWE-203

References

Other References

https://access.redhat.com/security/cve/CVE-2026-88834 https://bugzilla.redhat.com/show_bug.cgi?id=2531348

Frequently Asked Questions

What is CVE-2026-88834? +

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. It has a CVSS v3.1 base score of 3.7 (LOW).

How severe is CVE-2026-88834? +

CVE-2026-88834 has a CVSS v3.1 score of 3.7 out of 10, rated LOW. This is a low-severity vulnerability with limited impact. The EPSS score is 0.0022, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-88834? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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