Skip to main content
Menu
CVEs

CVE

Busybox: httpd password rule bypass for pre-compressed .gz files via accept-encoding: gzip

CVE-2026-124738EUVD-2026-123357

5.3MediumCNA
Exploited
No known exploitation
Fix
See vendor advisory
Who is exposed
Not reported
Published
Last modified
Reference
Last checked
37/100 · provisional
None on Exploit-DB, Metasploit or GitHub

Summary

BusyBox's httpd web server, as shipped in Red Hat Enterprise Linux 6 and Red Hat Hardened Images, checks passwords against the requested path rather than the pre-compressed file it actually serves. A remote attacker, without logging in, can request an uncompressed path with gzip encoding to get past password rules set for the compressed file and read sensitive files.

Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.

Read the original description

A flaw was found in BusyBox. When the HTTP daemon (httpd) has pre-compressed file support enabled, authentication checks are evaluated only against the requested URL path rather than the pre-compressed file being served. A remote attacker can exploit this flaw by requesting an uncompressed file path while specifying gzip encoding, bypassing password rules configured specifically for the compressed file. This vulnerability can lead to unauthorized information disclosure of sensitive files.

cve.now Index

37Pcve.now Index 37 of 100 · methodology v3 · provisional
  • Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
  • Exposure17/25No login or user action needed per the CVSS vector, reachable over the network without a login · Unknown: No advisory context yet
  • Reach10/20Shipped in major Linux distributions
  • Severity5.3/10CVSS 5.3
  • No patch5/5No fixed version listed; see vendor advisory

What would change the score

  • Would score about 82 if added to CISA KEV
  • Would score about 77 if CISA's SSVC rates exploitation active
  • Would score about 42 if advisories confirm default setups are exposed

Check your systems with an agent

Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.

Check whether my systems are affected by CVE-2026-124738 (Busybox: httpd password rule bypass for pre-compressed .gz files via accept-encoding: gzip), using the cve.now data below.

Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.

What cve.now has for CVE-2026-124738 (entry last updated 2026-11-11):
Affected:
- Red Hat Red Hat Enterprise Linux 6: version range not reported
- Red Hat Red Hat Hardened Images: version range not reported
Fixed versions: none listed yet.
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
CISA KEV: CVE-2026-124738 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-124738 only. If you also check another CVE, look up its own KEV status; never assume it from this one.

How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.

Verify against the linked advisories before concluding, and cite the date you read each one:
- https://bugzilla.redhat.com/show_bug.cgi?id=2571610
- https://access.redhat.com/security/cve/CVE-2026-124738
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.

Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.

Entry: https://cve.now/CVE-2026-124738
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-124738"}.

Timeline

  1. CVE published
  2. First seen by cve.now
  3. Record last updated

Affected versions

  • busybox

    Version range not reported

  • busybox

    Version range not reported

Evidence 4

CVE record · 2

Establishes: The identifier and description.

  1. Record
  2. Record

Write-ups · 1

Establishes: Technical detail and context.

  1. Report

Other links · 1

  1. Link

Corrections

None so far.

Something wrong on this page? Report an error. Every fix is listed here.