CVE-2026-12249 Affecting adsys package, versions <0.16.3
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-UBUNTU2510-ADSYS-17400980
- published23 Jun 2026
- disclosed22 Jun 2026
Introduced: 22 Jun 2026
CVE-2026-12249 (opens in a new tab)How to fix?
Upgrade Ubuntu:25.10 adsys to version 0.16.3 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream adsys package and not the adsys package as distributed by Ubuntu.
See How to fix? for Ubuntu:25.10 relevant fixed versions and status.
An issue was discovered in Canonical ADSys upstream versions through v0.16.2. During Active Directory Certificate Services (AD CS) certificate auto-enrollment via the vendored Samba client script (internal/policies/certificate/python/vendor_samba/gp/gp_cert_auto_enroll_ext.py), ADSys utilizes a plaintext HTTP connection (http://) instead of a secure HTTPS connection (https://) to request the CA certificate from the Active Directory Certificate Services server (GetCACert). An unauthenticated network attacker positioned between the managed Ubuntu host and the configured AD CS CA hostname can conduct a Man-in-the-Middle (MITM) attack. By intercepting the plaintext HTTP request, the attacker can supply an arbitrary, attacker-controlled Root CA certificate. Because the system automatically accepts this certificate and registers it into the local system trust store via update-ca-certificates, this results in system-wide trust store poisoning. Consequently, TLS clients utilizing the operating system trust store on the affected machine will accept rogue certificates for arbitrary domains, enabling persistent decryption and interception of subsequent TLS connections. This issue is resolved in version v0.16.3.