CVE-2026-84641

A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID response. Heap contents can ultimately be persisted to prefs.js. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2...

CVE-2026-84641

A use-after-free in Mozilla Thunderbird's IMAP ID response handling allows a malicious IMAP server to trigger heap-memory disclosure. The leaked heap contents can ultimately be persisted to prefs.js , enabling an attacker to recover sensitive data without user interaction. The vulnerability carri...

CVE-2026-84641 Information disclosure due to malicious IMAP server response

A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID response. Heap contents can ultimately be persisted to prefs.js. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2...

CVE-2026-84641

A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID response. Heap contents can ultimately be persisted to prefs.js. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2...

CVE-2026-42391

A flaw was found in Dovecot. An unauthenticated attacker can send an IMAP ID command with a very large number of parameters before logging in. This action causes the server to consume excessive memory and CPU resources, leading to the termination of login processes and other active connections...

CVE-2026-40203

A flaw was found in dovecot where, when IMAP compression is enabled, the system reuses the same compression state across responses within a session. This allows a remote attacker, who can send mail to a user and monitor the sizes of their IMAP traffic, to potentially deduce the content of small...

CVE-2026-73209

A flaw was found in Dovecot. An authenticated attacker can send specially crafted compressed data, leading to the affected process exhausting its stack and crashing. This termination of the process can result in degradation or a complete denial of service for the IMAP Internet Message Access...

CVE-2026-52687

A flaw was found in dovecot. A remote attacker with valid credentials can exploit this vulnerability by selecting a compression algorithm for the IMAP connection that requires a large amount of memory for decompression. By opening several such connections, the attacker can exhaust the process's...

CVE-2026-42392

A flaw was found in Dovecot. An attacker with valid credentials can send an invalid IMAP URLFETCH command, leading to the inclusion of uninitialized memory in the error response. This can disclose process memory contents to the client, potentially revealing sensitive data. Mitigation To mitigate...

CVE-2026-40017

A flaw was found in Dovecot. A remote attacker who can send mail to a user can craft a message header designed to cause collisions in an internal hash table. This manipulation forces the IMAP THREAD command to consume excessive CPU resources, leading to degradation or a complete denial of service...

CVE-2026-40015

A flaw was found in Dovecot's imap-hibernate service. An authenticated attacker can open numerous connections and send malformed commands, leading to an out-of-bounds read. This can intermittently crash the process, interrupting hibernated IMAP sessions and causing a denial of service for affecte...

CVE-2026-40014

A flaw was found in Dovecot. A remote attacker, by sending a specially crafted email message header to a user, can cause the Internet Message Access Protocol IMAP THREAD command to consume excessive CPU resources. When a mail client processes this message, it can lead to degradation or a denial o...

CVE-2026-33607

A flaw was found in Dovecot. An authenticated attacker can exploit a vulnerability in the IMAP LIST command to consume excessive CPU resources. This can lead to a degradation of service or a complete denial of service DoS for the IMAP server, impacting the availability of email services. Mitigati...

Security Vulnerabilities fixed in Thunderbird 155 — Mozilla

Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. A maliciously constructed mail header could lead to a one byte read past the end of a buffer. A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID...

Security Vulnerabilities fixed in Thunderbird 153.2 — Mozilla

Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. A maliciously constructed mail header could lead to a one byte read past the end of a buffer. A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID...

Mozilla Thunderbird < 140.15

The version of Thunderbird installed on the remote Windows host is prior to 140.15. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-87 advisory. - Privilege escalation due to invalid pointer in the Graphics component. This vulnerability was fixed in Firefox 15...

Mozilla Thunderbird < 153.2

The version of Thunderbird installed on the remote macOS or Mac OS X host is prior to 153.2. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-88 advisory. - Privilege escalation due to invalid pointer in the Graphics component. This vulnerability was fixed in...

Mozilla Thunderbird < 155.0

The version of Thunderbird installed on the remote macOS or Mac OS X host is prior to 155.0. It is, therefore, affected by multiple vulnerabilities as referenced in the mfsa2026-86 advisory. - Privilege escalation due to invalid pointer in the Graphics component. This vulnerability was fixed in...

Security Vulnerabilities fixed in Thunderbird 140.15 — Mozilla

Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. A maliciously constructed mail header could lead to a one byte read past the end of a buffer. A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID...

PT-2026-84527

Name of the Vulnerable Software and Affected Versions Thunderbird versions prior to 140.15 Thunderbird versions prior to 153.2 Thunderbird versions prior to 155 Description A malicious IMAP server can trigger a use-after-free a situation where a program continues to use a pointer after it has bee...