Quick answers
- Is CVE-2026-124738 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-124738 being exploited in the wild.
- How severe is CVE-2026-124738?
- Medium severity, with a CVSS score of 5.3, published 11 November 2026.
- Which products and versions are affected?
- BusyBox <unknown.
- Is there a fix for CVE-2026-124738?
- No fixed version is recorded yet. Configure authentication rules at the directory level rather than individual file paths, or apply password rules for both uncompressed filenames and their .gz variants. Alternatively, restrict network reachability to the BusyBox httpd daemon using local firewall rules if remote access is not required.</anigation> <parameter name="timeline">[{"kind": "disclosed", "at": "2026-11-11"}] If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-124738 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-124738?
- Check whether you run BusyBox at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
Configure authentication rules at the directory level rather than individual file paths, or apply password rules for both uncompressed filenames and their .gz variants. Alternatively, restrict network reachability to the BusyBox httpd daemon using local firewall rules if remote access is not required.</anigation> <parameter name="timeline">[{"kind": "disclosed", "at": "2026-11-11"}]
Technical details
A flaw in BusyBox httpd evaluates authentication checks against the requested URL path rather than the actual pre-compressed file being served. An attacker can exploit this by requesting an uncompressed file path while specifying gzip encoding in the Accept-Encoding header, causing the server to serve the compressed variant while bypassing password rules configured for that compressed file. The vulnerability requires pre-compressed file support to be enabled and authentication rules to target individual file paths rather than directories.
Affected products
- BusyBox <unknown