CVE-2020-25275 Denial of service in n/a

What is CVE-2020-25275?

CVE-2020-25275 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 4 Jan 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Dovecot before 2.3.13 has Improper Input Validation in lda, lmtp, and imap, leading to an application crash via a crafted email message with certain choices for ten thousand MIME parts.

Weakness: CWE-20

Which versions are affected by CVE-2020-25275?

It affects 3 products.

Products include Debian Debian Linux, Dovecot Dovecot, Fedoraproject Fedora.

How do I fix CVE-2020-25275?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2020-25275 being exploited?

There is no known exploitation of CVE-2020-25275 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2020-25275, DEBIAN-CVE-2020-25275, GHSA-jv8c-8hrc-9f7m, UBUNTU-CVE-2020-25275, USN-4674-2.