CVE-2026-73476: Improper Handling of Case Sensitivity vulnerability in Drupal External Authentication allows Privilege Escalat

Routine

MEDIUM 5.4UPGRADE

CVE-2026-73476 is a medium-severity flaw (CVSS 5.4) affecting external authentication. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Improper Handling of Case Sensitivity vulnerability in Drupal External Authentication allows Privilege Escalation. This issue affects External Authentication versions: from 0.0.0 to 2.0.13.

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	5.4 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.3% (top 78%)
CISA exploited list	No
Weakness	CWE-178
Published	2026-09-02
Last modified	2026-09-15

Publisher (CNA): Drupal.org · Vendor: external authentication project

Last updated 2026-09-15 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-09-02 13:18 UTCPublished CVE record published
2026-09-15 12:28 UTCUpdated Record last modified

external authentication project external authentication UPGRADE

Affected: < 2.0.13 · >= 8.x-1.0 and <= 8.x-1.4

Fixed in: 2.0.13

Safe to downgrade to: a release before 8.x-1.0

1. Check installed version

apt-cache policy external-authentication || rpm -q external-authentication || external-authentication --version

2. UPGRADE to 2.0.13 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade external-authentication

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade external-authentication

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 8.x-1.0 (Debian / Ubuntu)

apt-cache madison external-authentication sudo apt install external-authentication=<VERSION_BEFORE_8.x-1.0> sudo apt-mark hold external-authentication

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list external-authentication sudo dnf downgrade external-authentication-<VERSION_BEFORE_8.x-1.0> sudo dnf versionlock add external-authentication

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

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-2026-73476?

external authentication: upgrade to 2.0.13. Exact commands for each OS are on this page.

Is CVE-2026-73476 being exploited?

CVE-2026-73476 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-2026-73476 affect?

CVE-2026-73476 affects external authentication. Severity is medium (CVSS 5.4). Improper Handling of Case Sensitivity vulnerability in Drupal External Authentication allows Privilege Escalation. This issue affects External Authentication versions: from 0.0.0 to 2.0.13.

How urgent is CVE-2026-73476?

Priority 24/100. No elevated risk signals yet.

Software pages

Drupal vulnerabilities

References

← Back to latest CVEs