CVE-2026-11405: The web server binary /bin/httpd contains a hidden backdoor authentication mechanism in the login() function a

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CRITICAL 9.8REMOTE

CVE-2026-11405 is a critical-severity flaw (CVSS 9.8) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The web server binary /bin/httpd contains a hidden backdoor authentication mechanism in the login() function at 004c88b8. - The function contains a normal authentication path using MD5/hash-based password verification (prod_encode64/PasswordToMd5/check_rand_key). - After normal authentication fails, it calls GetValue("sys.rzadmin.password") to read a backdoor password from the device configuration. - It performs a direct strcmp() comparison

Why this priority

Critical severity
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.8% (top 45%)
CISA exploited list	No
Published	2026-07-06
Last modified	2026-10-25

Publisher (CNA): CERT/CC

Last updated 2026-10-25 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Timeline

2026-07-06 20:16 UTCPublished CVE record published
2026-10-25 20:10 UTCUpdated Record last modified

Exact fixes by distribution

Fedora 46 · python-apprise · FIXED · 2.1.0-1.fc46 · FEDORA-2026-ef67a72c5d · source

sudo dnf upgrade --advisory=FEDORA-2026-ef67a72c5d

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

GitHub PoC: HORKimhab/CVE-2026-11405 (0 stars)

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-11405?

No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.

Is CVE-2026-11405 being exploited?

CVE-2026-11405 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-11405 affect?

CVE-2026-11405 affects affected software. Severity is critical (CVSS 9.8). The web server binary /bin/httpd contains a hidden backdoor authentication mechanism in the login() function at 004c88b8. - The function contains a normal authentication path using MD5/hash-based password verification (prod_encode64/Pass

How urgent is CVE-2026-11405?

Priority 56/100. Critical severity; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

Software pages

Apache HTTP Server vulnerabilities

References

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