CVE-2017-16944 Denial of service in n/a

What is CVE-2017-16944?

CVE-2017-16944 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 25 Nov 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

The receive_msg function in receive.c in the SMTP daemon in Exim 4.88 and 4.89 allows remote attackers to cause a denial of service (infinite loop and stack exhaustion) via vectors involving BDAT commands and an improper check for a '.' character signifying the end of the content, related to the bdat_getc function.

Weakness: CWE-835

Which versions are affected by CVE-2017-16944?

It affects 2 products.

Products include Debian Debian Linux, Exim Exim.

How do I fix CVE-2017-16944?

Apply the vendor's patch.

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-2017-16944 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2017-16944 exists.

Public exploit code: 1 Exploit-DB entry.

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 CLEANSTART-2025-UI48931, DEBIAN-CVE-2017-16944, GHSA-vpr2-5gxq-hjc6.