CVE-2012-0214 in apt
Summary
by MITRE
The pkgAcqMetaClearSig::Failed method in apt-pkg/acquire-item.cc in Advanced Package Tool (APT) 0.8.11 through 0.8.15.10 and 0.8.16 before 0.8.16~exp13, when updating from repositories that use InRelease files, allows man-in-the-middle attackers to install arbitrary packages by preventing a user from downloading the new InRelease file, which leaves the original InRelease file active and makes it more difficult to detect that the Packages file is modified and unsigned.
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Analysis
by VulDB Data Team • 05/10/2026
The vulnerability described in CVE-2012-0214 represents a critical security flaw in the Advanced Package Tool (APT) package management system used extensively in debian-based linux distributions. This vulnerability specifically affects APT versions between 0.8.11 and 0.8.15.10, as well as versions prior to 0.8.16~exp13, creating a window of exposure where system integrity can be compromised through sophisticated man-in-the-middle attacks. The flaw resides in the pkgAcqMetaClearSig::Failed method within the apt-pkg/acquire-item.cc source file, which governs how APT handles metadata verification during package updates.
The technical mechanism of this vulnerability involves the manipulation of InRelease files that are crucial for package authenticity verification in modern APT implementations. When a user attempts to update packages from repositories that utilize InRelease files, the vulnerable APT version fails to properly handle download failures or network interruptions. Specifically, if an attacker can prevent the download of a new InRelease file during an update process, the system retains the original InRelease file rather than properly failing the update operation. This behavior creates a false sense of security for users while simultaneously allowing malicious actors to install unsigned packages that could contain malware or backdoors.
The operational impact of this vulnerability extends beyond simple package management compromise, as it directly undermines the fundamental security model of package verification in linux systems. When the original InRelease file remains active despite failed updates, the system continues to trust package lists that may have been modified by attackers, effectively bypassing cryptographic signature verification mechanisms. This vulnerability aligns with CWE-310, which addresses cryptographic weaknesses, and represents a significant deviation from the expected behavior of secure package management systems. The attack vector specifically targets the trust model of package repositories, making it particularly dangerous in environments where automated updates are enabled and network traffic can be intercepted.
From an attack perspective, this vulnerability enables persistent man-in-the-middle attacks where adversaries can manipulate package repositories without immediate detection. The attack scenario involves intercepting network traffic between the client system and package repositories, preventing the download of updated InRelease files, and allowing the system to continue operating with potentially compromised package lists. This approach leverages the trust relationship between package managers and repositories, making it difficult for users to detect malicious activity. The vulnerability demonstrates a critical flaw in error handling and fallback mechanisms within APT's package acquisition process, as outlined in ATT&CK technique T1547.006 for process injection and T1068 for exploit for privilege escalation.
The mitigation strategies for this vulnerability involve immediate patching of affected APT versions to ensure proper handling of InRelease file failures and implementation of robust network security measures. System administrators should prioritize updating to patched versions of APT that properly invalidate cached metadata when download failures occur. Additionally, organizations should implement network monitoring to detect unusual patterns in package repository communications and consider implementing additional verification mechanisms beyond the standard InRelease file validation. The vulnerability serves as a reminder of the critical importance of proper error handling in security-critical systems and the necessity of robust fallback mechanisms when cryptographic verification fails.