CVE-2019-10149
Exim Mail Transfer Agent (MTA) Improper Input Validation
Exim Mail Transfer Agent (MTA)
A flaw was found in Exim versions 4.87 to 4.91 (inclusive). Improper validation of recipient address in deliver_message() function in /src/deliver.c may lead to remote command execution.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 10 January 2022. US federal agencies were required to remediate it by 10 July 2022.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 100%, which is higher than 99.9% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2019-10149 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2019-10149.
What does CVE-2019-10149 affect?
CVE-2019-10149 affects Exim Mail Transfer Agent (MTA). A flaw was found in Exim versions 4.87 to 4.91 (inclusive). Improper validation of recipient address in deliver_message() function in /src/deliver.c may lead to remote command execution.
How severe is CVE-2019-10149?
CVE-2019-10149 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 100%, higher than 99.9% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 10 July 2022.
How should organisations respond to CVE-2019-10149?
Apply the vendor patch for Exim Mail Transfer Agent (MTA) as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.