CVE-2022-1328 in Mutt
Summary
by MITRE • 04/15/2022
Buffer Overflow in uudecoder in Mutt affecting all versions starting from 0.94.13 before 2.2.3 allows read past end of input line
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 04/06/2026
The vulnerability identified as CVE-2022-1328 represents a critical buffer overflow condition within the uudecoder functionality of the Mutt email client application. This issue affects versions beginning with 0.94.13 up to but not including 2.2.3, creating a persistent security risk across multiple releases of this widely-used email client. The flaw manifests specifically within the uudecoder component responsible for processing uuencoded attachments and data streams, where improper input validation leads to memory corruption vulnerabilities.
The technical implementation of this buffer overflow stems from inadequate bounds checking during the processing of input lines within the uudecoder module. When Mutt encounters uuencoded data, it reads input lines and attempts to decode them according to the standard uuencoding format. However, the vulnerable code fails to properly validate the length of input lines against the allocated buffer space, allowing attackers to craft malicious input that exceeds the expected buffer boundaries. This condition specifically enables read operations that extend beyond the end of the input line, resulting in memory access violations that can be exploited for arbitrary code execution.
The operational impact of CVE-2022-1328 extends beyond simple denial of service scenarios, as it provides potential attackers with opportunities for remote code execution within the context of the Mutt application. Since Mutt is commonly used in server environments and automated email processing systems, exploitation of this vulnerability could allow remote attackers to execute arbitrary commands on affected systems. The vulnerability is particularly concerning because it operates at the decoding layer where email attachments are processed, meaning that simply receiving a maliciously crafted email could trigger the buffer overflow condition without requiring user interaction beyond opening the message.
Security researchers have classified this vulnerability according to the Common Weakness Enumeration framework as CWE-121, which describes heap-based buffer overflow conditions, and potentially CWE-787, which covers out-of-bounds write operations. The attack pattern aligns with the MITRE ATT&CK framework under the T1190 technique for Exploit Public-Facing Application, as this vulnerability affects a widely deployed email client that serves as a common attack surface. The exploitation requires careful crafting of uuencoded data that triggers the specific buffer boundary condition, making it a sophisticated but achievable attack vector for determined threat actors.
Mitigation strategies for CVE-2022-1328 primarily focus on immediate version upgrades to Mutt 2.2.3 or later, which contain the necessary patches to address the buffer overflow condition. System administrators should prioritize patching affected installations, particularly in environments where Mutt processes untrusted email content or serves as part of automated email workflows. Additional defensive measures include implementing email filtering rules that identify and quarantine uuencoded attachments, deploying network-based intrusion detection systems to monitor for exploitation attempts, and considering the implementation of email sandboxing techniques that isolate email processing from core system resources. Organizations should also conduct thorough vulnerability assessments to identify all systems running affected Mutt versions and establish monitoring procedures to detect potential exploitation attempts.