SB2019050508 - Input validation error in dovecot (Alpine package)

Description

This security bulletin contains information about 1 security vulnerability.

1) Input validation error (CVE-ID: CVE-2019-10691)

The vulnerability allows a remote attacker to perform denial of service (DoS) attack.

The vulnerability exists due to improper input validation of user-supplied characters in UTF-8 encoding within the JSON encoder. A remote unauthenticated attacker can supply a specially crafted string that contains invalid UTF-8 characters via a username during authentication process or via “From” or “Subject” headers in an email (if OX push notification driver is enabled) and crash the affected server.

Successful exploitation of the vulnerability will result in denial of service (DoS) attack.

Remediation

Install update from vendor's website.

References

• https://git.alpinelinux.org/aports/commit/?id=4cbff22201d9f2fb21d860bae0e62f3bf814ed45
• https://git.alpinelinux.org/aports/commit/?id=7f9b5fbadaf37d0e9b4a716239593edb14d4db6b
• https://git.alpinelinux.org/aports/commit/?id=f82ad4a4bd0bcfe6c75ff43189ad29dc14c38add