Описание
Security update for dovecot22
This update for dovecot22 fixes the following issues:
Security issues fixed:
- CVE-2026-27852: DoS by sending mail with bad header (bsc#1276799).
- CVE-2026-33604: SMTP smuggling via missing dot-stuffing after bare carriage return (bsc#1276802).
- CVE-2026-33605:
managesieve-login: pre-auth crash (bsc#1276809). - CVE-2026-33606:
dsync: mail content can causedsyncprotocol injection (bsc#1276800). - CVE-2026-33607: IMAP
LISTmatch_sub()exponential backtracking leading to CPU denial of service (bsc#1276795). - CVE-2026-40014: CPU DoS via crafted references header (bsc#1276804).
- CVE-2026-40015:
imap-hibernatecan be crashed (bsc#1276812). - CVE-2026-40019:
managesieve-loginpre-auth infinite loop (bsc#1276811). - CVE-2026-40203: IMAP compression can reveal whether a small synced email body matches sender-chosen text (bsc#1276815).
- CVE-2026-42007:
sieveeditheaderRCE (bsc#1276817). - CVE-2026-42391:
imap: pre-login memory/CPU growth withIDcommand (bsc#1276835). - CVE-2026-42393:
doveadm_passwordor api key length can be leaked with timing comparisons (bsc#1276827). - CVE-2026-52687:
imap:COMPRESS ZSTDcan cause excessive memory usage (bsc#1276837). - CVE-2026-73209:
imap-logincrash due to self-recursion on zero-output decompress chunks (bsc#1276833). - multiple security fixes (bsc#1276792).
Other updates and bugfixes:
- Non-CVE hardening taken from the same upstream release:
sieve: requiring the same extension repeatedly grew the default argument override chain, which is walked recursively - a crafted script could overflow the stacksieve:${unicode:...}hex values could overflow anunsigned intand wrap back into the valid Unicode range; the hex parser also read one byte past the end of the buffersievevariables: the${1234...}numeric index overflowed asigned intsieve enotify: a single script could emit an unlimited number of notification messages; limited to 10 as upstream does
Список пакетов
SUSE Linux Enterprise Server 12 SP5-LTSS
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5
Ссылки
- Link for SUSE-SU-2026:3919-1
- E-Mail link for SUSE-SU-2026:3919-1
- SUSE Security Ratings
- SUSE Bug 1276792
- SUSE Bug 1276795
- SUSE Bug 1276799
- SUSE Bug 1276800
- SUSE Bug 1276802
- SUSE Bug 1276804
- SUSE Bug 1276809
- SUSE Bug 1276811
- SUSE Bug 1276812
- SUSE Bug 1276815
- SUSE Bug 1276817
- SUSE Bug 1276827
- SUSE Bug 1276833
- SUSE Bug 1276835
- SUSE Bug 1276837
- SUSE CVE CVE-2026-27852 page
- SUSE CVE CVE-2026-33604 page
Описание
An attacker that can send mail to a user can craft a message whose headers contain a very large number of email addresses or MIME parameters, which causes excessive memory usage when the message is later parsed. The message is still delivered, but reading it over IMAP can exhaust the memory limit of the process and terminate it, causing denial of service for the affected user. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-27852
- SUSE Bug 1276792
- SUSE Bug 1276799
Описание
An attacker that can get Dovecot to relay a message, for example through Sieve redirect or submission relay, can use a crafted line ending in the message body to bypass the outbound protection that prevents message content from being interpreted as SMTP commands. A downstream mail server that hasn't yet fixed the SMTP smuggling vulnerability can be tricked into treating part of the message body as new SMTP commands, allowing injection of spoofed email. This is the same vulnerability class as CVE-2023-51764 and CVE-2023-51766. Where you control the receiving mail servers, ensure they reject bare carriage returns in message data. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-33604
- SUSE Bug 1276792
- SUSE Bug 1276802
Описание
An unauthenticated attacker can crash the ManageSieve login process by sending a small malformed command before authenticating. If running in high-security mode (default for community releases), only the attacker's own connection is terminated. If running in high-performance mode (default for Pro releases), all connections handled by the same managesieve-login process are terminated. Repeating the attack can cause denial of service for Sieve script management. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-33605
- SUSE Bug 1276792
- SUSE Bug 1276809
Описание
Mail content stored by a user can be crafted so that it is interpreted as dsync protocol commands when an administrator later runs dsync with the stream protocol, for example during a migration. Injected commands can modify mailbox state on the destination during migration or replication, including internal mailbox attributes that a user should not be able to set directly. It can also cause dsync errors. Avoid running dsync with the stream protocol on mailboxes with untrusted content. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-33606
- SUSE Bug 1276792
- SUSE Bug 1276800
Описание
An attacker that has valid credentials can use IMAP LIST command to consume CPU. This can cause degradation or denial of service for IMAP. Monitor system for abnormal CPU usage and kill the offending process and lock account. Alternatively install fixed version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-33607
- SUSE Bug 1276792
- SUSE Bug 1276795
Описание
An attacker that can send mail to a user can craft a message header that makes the IMAP THREAD command consume CPU disproportionate to the size of the message. When a mail client issues a THREAD command on the affected mailbox, this can cause degradation or denial of service for IMAP. Monitor system for abnormal CPU usage, kill the offending process and remove the offending message from the affected mailbox. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-40014
- SUSE Bug 1276792
- SUSE Bug 1276804
- SUSE Bug 1276813
Описание
An attacker that has valid credentials can open many connections to the imap-hibernate service and send invalid commands, which can intermittently cause an out-of-bounds read and crash the process. The crash interrupts hibernated IMAP sessions handled by the affected process, which can cause degradation of service for IMAP. Disable IMAP hibernation. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-40015
- SUSE Bug 1276792
- SUSE Bug 1276812
Описание
An unauthenticated attacker can send a truncated quoted argument to the ManageSieve login process, which makes it spin in an infinite loop consuming CPU. This can cause degradation or denial of service for Sieve script management, and repeated connections can consume all available CPU on the server. Monitor system for abnormal CPU usage and kill the offending process. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-40019
- SUSE Bug 1276792
- SUSE Bug 1276811
Описание
When IMAP compression is enabled, the same compression state is reused across responses in a session, so response sizes depend on both attacker-supplied mail and other mail in the same mailbox. An attacker that can send mail to a user and can also observe the sizes of that user's IMAP traffic can confirm whether the body of a small message matches a guessed text. Recovery of arbitrary unknown content was not demonstrated, but the attack can disclose whether a secret-like message body matches a candidate. Disable IMAP compression. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-40203
- SUSE Bug 1276792
- SUSE Bug 1276815
Описание
An attacker that has valid credentials can use a Sieve script with the editheader extension to trigger a use-after-free in the mail editing code, and to write memory contents beyond the intended buffer into the delivered mail. This causes memory leak and opportunity to do memory corruption during mail delivery, which can crash the delivery process and may allow execution of arbitrary code in the context of that process. Disable the Sieve editheader extension. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-42007
- SUSE Bug 1276792
- SUSE Bug 1276817
Описание
An unauthenticated attacker can send an IMAP ID command with a very large number of parameters before logging in, which causes memory and CPU usage to grow disproportionately. The login process can be terminated by the out-of-memory handling, which also terminates all other connections handled by the same process. This can cause degradation or denial of service for IMAP logins. Limit the number of connections handled by a single imap-login process. This has a performance impact though. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-42391
- SUSE Bug 1276792
- SUSE Bug 1276835
Описание
The comparison used for the doveadm password and API key is not fully timing safe and can reveal the length of the configured secret. An attacker with access to the same network as the doveadm service, able to make repeated requests and measure response timing accurately, can learn the length of the secret, which reduces the effort needed to guess it. The secret value itself is not disclosed. Restrict network access to the doveadm service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-42393
- SUSE Bug 1276792
- SUSE Bug 1276827
Описание
An attacker that has valid credentials can select a compression algorithm for the IMAP connection whose decompression state requires a large amount of memory, and open several such connections. The memory limit of the process is reached with only a few connections, terminating the process and all connections it handles, which can cause degradation or denial of service for IMAP. Disable IMAP compression. Alternatively limit the number of connections handled by a single imap-login process, though this has a performance impact. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-52687
- SUSE Bug 1276792
- SUSE Bug 1276837
Описание
An attacker that has valid credentials can send crafted compressed data that causes the affected process to exhaust its stack and crash. The affected process is terminated, which can cause degradation or denial of service for IMAP. Update to non-vulnerable version. No publicly available exploits are known.
Затронутые продукты
Ссылки
- CVE-2026-73209
- SUSE Bug 1276792
- SUSE Bug 1276833