⚠ Reference material — not professional advice. Test in staging, back up first, verify against your specific version. Use your own judgment for your environment.
● High · CVSS 7

How to Fix CVE-2026-26158: Arbitrary File Read in Red Hat Hardened Images

Other vulnerabilities in the same area that are worth patching alongside this one:

*By Sai Kiran Pandrala*

⚡ At a glance
SeverityCVSS 7 - High
Actively exploited?Not currently listed in CISA KEV
AffectedRed Hat Hardened Images - see advisory for affected version ranges
Fixed in1.37.0-7.2.hum1
Type (CWE)CWE-73: External Control of File Name or Path

What is CVE-2026-26158?

CVE-2026-26158 is an arbitrary file read flaw in Red Hat Hardened Images. An authenticated or unauthenticated request can read files outside the intended path scope, exposing configuration, secrets, or other sensitive content. Vendor description: A flaw was found in BusyBox. This vulnerability allows an attacker to modify files outside of the intended extraction directory by crafting a malicious tar archive containing unvalidated hardlink or symlink entries.

Why this CVE matters

Arbitrary file read against a management product almost always exposes credentials, session secrets, or configuration. Treat any disclosure of this kind as a credential-rotation event in addition to a patching event.

For deployments of Red Hat Hardened Images that have been exposed to the public internet during the disclosure window, the operating assumption should be that scanning has already happened. Even where exploitation has not been publicly observed, scanning for the vulnerable fingerprint is cheap and routine. Patching closes the door; log review and credential rotation close out the rest of the response.

Am I affected?

Check your installed Red Hat Hardened Images version against the affected ranges in the vendor advisory linked below. If you cannot determine the version, treat the system as potentially affected and apply the patched build.

Open Red Hat Hardened Images's About dialog or run the vendor-documented version-check command. Compare the result against the affected ranges in the advisory.

How to fix CVE-2026-26158

  1. Read the vendor advisory in full: https://access.redhat.com/errata/RHSA-2026:13831
  2. Upgrade Red Hat Hardened Images to 1.37.0-7.2.hum1 or a later version listed in the vendor advisory.
  3. Back up the configuration (and database, where applicable) before upgrading.
  4. Apply the patch in a maintenance window. For HA pairs, upgrade the standby node first, fail over, then upgrade the former primary.
  5. Restart the affected service so the patched binary loads, then verify the new version (see verification section).

Patched-version commands

Vendor advisory: https://access.redhat.com/errata/RHSA-2026:13831

Affected: see Am I affected? above

Patched in: 1.37.0-7.2.hum1


# Vendor advisory: https://access.redhat.com/errata/RHSA-2026:13831
# Affected: see Am I affected? above
# Patched in: 1.37.0-7.2.hum1

# Debian / Ubuntu.
sudo apt update
sudo apt install --only-upgrade red-hat-hardened-images
dpkg -s red-hat-hardened-images | grep -i version

# RHEL / Rocky / AlmaLinux / Fedora.
sudo dnf upgrade red-hat-hardened-images
rpm -q red-hat-hardened-images

# openSUSE.
sudo zypper update red-hat-hardened-images

# Verify the running version matches 1.37.0-7.2.hum1 from the advisory.
red-hat-hardened-images --version 2>/dev/null || true


# Windows: pull the latest cumulative updates that include this CVE's fix.
Install-Module PSWindowsUpdate -Force -SkipPublisherCheck -Confirm:$false
Get-WindowsUpdate -AcceptAll -Install -AutoReboot
Get-HotFix | Sort-Object InstalledOn -Desc | Select-Object -First 5

Verify the fix landed


# Vendor advisory: https://access.redhat.com/errata/RHSA-2026:13831
# Post-patch verification (replace <service> with the real service unit).
journalctl -u <service> --since "10 minutes ago"
dmesg --since "10 minutes ago"

# Re-scan with your vulnerability scanner (Nessus, Qualys, Tenable, OpenVAS).
# It should no longer flag CVE-2026-26158 on the patched target.

If you cannot patch immediately

No official workaround exists beyond restricting network exposure to the affected component. Apply the vendor patch as the primary remediation.

How to verify the fix worked

If your installation was internet-reachable during the disclosure window, treat log review as part of the remediation rather than an optional follow-up. Look for unusually long URI paths containing traversal sequences, unexpectedly large responses from the affected endpoint, and outbound requests from the application to internal addresses or cloud-metadata endpoints. Treat any sensitive file the bug could disclose as exposed.

Frequently asked questions

Is CVE-2026-26158 being exploited in the wild?

Public exploitation has not been confirmed by CISA at the time of writing. Treat the patch as time-sensitive anyway; reports often lag actual abuse.

Will a WAF or IDS rule fully mitigate CVE-2026-26158?

No. Network-layer filters can reduce noise and slow opportunistic scanners, but they will not stop a determined attacker. The vendor patch is the only durable fix.

How long should I plan for the upgrade?

Typical vendor-documented upgrade windows for Red Hat Hardened Images run from a few minutes to under an hour depending on cluster size. Test in a staging environment first and follow the vendor's documented HA upgrade order.

References

*This guide was assembled from the official vendor advisory, the NVD record, and the CISA KEV catalog entry on 2026-05-25. Always confirm against the vendor advisory before applying changes in production.*