CVE-2019-16928: Exim Out-of-bounds Write Vulnerability
Exim 4.92 through 4.92.2 allows remote code execution, a different vulnerability than CVE-2019-15846. There is a heap-based buffer overflow in stringvformat in string.c involving a long EHLO command.
Other sources
Exim contains an out-of-bounds write vulnerability which can allow for remote code execution.
— CISA
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/exim4to a version that resolves this vulnerability.Fixed in 4.94.2-7+deb11u3Fixed in 4.94.2-7+deb11u6Fixed in 4.96-15+deb12u10Fixed in 4.98.2-1+deb13u3Fixed in 4.98.2-1+deb13u4Fixed in 4.99.4-2
Event History
Frequently Asked Questions
What is CVE-2019-16928?
CVE-2019-16928 is an Exim vulnerability that allows remote code execution through a heap-based buffer overflow in string_vformat.
What is the severity of CVE-2019-16928?
CVE-2019-16928 is classified as critical with a severity value of 9.8.
Which software is affected by CVE-2019-16928?
Exim Internet Mailer versions 4.92 through 4.92.2, Canonical Ubuntu Linux 19.04, Debian Linux 10.0, and Fedora versions 29, 30, and 31 are affected by CVE-2019-16928.
How can I fix CVE-2019-16928?
To fix CVE-2019-16928, you should update to the latest versions of the affected software, such as Exim 4.92-8+deb10u6 or higher, Exim 4.92-8+deb10u8 or higher, Exim 4.94.2-7 or higher, Exim 4.94.2-7+deb11u1 or higher, Exim 4.96-15+deb12u1 or higher, Exim 4.96-15+deb12u2 or higher, or Exim 4.97~RC2-2 or higher, depending on your software version.
Where can I find more information about CVE-2019-16928?
You can find more information about CVE-2019-16928 at the following references: [Openwall 1](http://www.openwall.com/lists/oss-security/2019/09/28/1), [Openwall 2](http://www.openwall.com/lists/oss-security/2019/09/28/2), [Openwall 3](http://www.openwall.com/lists/oss-security/2019/09/28/3).