GHSA-mcg6-h362-cmq5
HIGHImproper Authorization in cobbler
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
cobblerReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Impact
If PAM is correctly configured and a user account is set to expired, the expired user-account is still able to successfully log into Cobbler in all places (Web UI, CLI & XMLRPC-API).
The same applies to user accounts with passwords set to be expired.
Patches
There is a patch for the latest Cobbler 3.3.2 available, however a backport will be done for 3.2.x.
Workarounds
- Delete expired accounts which are able to access Cobbler via PAM.
- Use
chage -l <username>to lock the account. If the account has SSH-Keys attached then remove them completely.
References
- Originally discovered by @ysf at https://www.huntr.dev/bounties/c458b868-63df-414e-af10-47e3745caa1d/
How to test if my Cobbler instance is affected?
The following pytest test assumes that your PAM setup is correct. In case the added user is not able to login, this test does not make sense to be executed.
def test_pam_login_with_expired_user():
# Arrange
# create pam testuser
test_username = "expired_user"
test_password = "password"
test_api = CobblerAPI()
subprocess_1 = subprocess.run(
["perl", "-e", "'print crypt(\"%s\", \"%s\")'" % (test_username, test_password)],
stdout=subprocess.PIPE
)
subprocess.run(["useradd", "-p", subprocess_1.stdout, test_username])
# change user to be expired
subprocess.run(["chage", "-E0", test_username])
# Act
result = pam.authenticate(test_api, test_username, test_password)
# Assert - login should fail
assert not result
For more information
If you have any questions or comments about this advisory:
- Open an issue in the Cobbler repository
- Ask in the Gitter/Matrix Chat
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | cobbler | all versions | 3.3.2 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for cobbler. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update cobbler to 3.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mcg6-h362-cmq5 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-mcg6-h362-cmq5 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-mcg6-h362-cmq5. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-mcg6-h362-cmq5 in your dependencies?
O3 detects GHSA-mcg6-h362-cmq5 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.