Описание
When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.
Пакеты
| Пакет | Статус | Версия исправления | Релиз | Тип |
|---|---|---|---|---|
| dovecot | fixed | 1:2.4.3+dfsg1-1 | package | |
| dovecot | fixed | 1:2.4.1+dfsg1-6+deb13u4 | trixie | package |
| dovecot | not-affected | bookworm | package | |
| dovecot | not-affected | bullseye | package |
Примечания
https://dovecot.org/mailman3/archives/list/dovecot-news@dovecot.org/thread/IKIHZX77IPTGSP5WBIPJUOFBUQFKVPE7/
https://documentation.open-xchange.com/dovecot/security/advisories/html/2026/oxdc-adv-2026-0001.html#cve-2025-59028-invalid-base64-authentication-can-cause-dos-for-other-logins
Introduced with: https://github.com/dovecot/core/commit/1486c30e191ff079bfa78e7950173bb33d8073d9 (2.4.1)
Fixed by: https://github.com/dovecot/core/commit/56df8acb5f21abaa039f91f1b0839a75719231de (2.4.3)
EPSS
Связанные уязвимости
When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.
When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.
When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.
When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.
EPSS