ArchLinux: 202106-56: dovecot: information disclosure
Summary
- CVE-2021-29157 (information disclosure)
A security issue has been found in Dovecot before version 2.3.14.1. The
kid and azp fields in JWT tokens are not correctly escaped. This may be
used to supply attacker controlled keys to validate tokens in some
configurations. The attack requires an attacker to be able to write
files to the local disk. As a result, a local attacker can login as any
user and access their emails.
- CVE-2021-33515 (information disclosure)
A security issue has been found in Dovecot before version 2.3.14.1. An
on-path attacker could inject plaintext commands before the STARTTLS
negotiation that would be executed after STARTTLS finished with the
client. Only the SMTP submission service is affected. As a result, an
attacker can potentially steal user credentials and emails. The
attacker needs to have sending permissions on the submission server (a
valid username and password).
Resolution
Upgrade to 2.3.15-1.
# pacman -Syu "dovecot>=2.3.15-1"
The problems have been fixed upstream in version 2.3.15.
References
https://dovecot.org/pipermail/dovecot-news/2021-June/000461.html https://github.com/dovecot/core/commit/7f06f6274437ea97142df1f64f322b3ced44d0b3 https://github.com/dovecot/core/commit/7a77e070ddb6a67fe7a40118ba3e3f9b6062a7d1 https://github.com/dovecot/core/commit/bae4e44596d6548322665d242b055f44fe1dc58d https://dovecot.org/pipermail/dovecot-news/2021-June/000462.html https://github.com/dovecot/core/commit/65bd1a27a361545c9ccf405b955c72a9c4d29b38 https://security.archlinux.org/CVE-2021-29157 https://security.archlinux.org/CVE-2021-33515
Workaround
CVE-2021-29157 can be mitigated by disabling local JWT validation inoauth2, or using a different dict driver than fs:posix. No knownworkaround exists for CVE-2021-33515.