CVE-2019-16928
KEVExim Out-of-bounds Write Vulnerability
Description
Exim contains an out-of-bounds write vulnerability which can allow for remote code execution.
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 string_vformat in string.c involving a long EHLO command.
CVSS 3.1 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HPublishedSep 27, 2019
Last modifiedJun 17, 2026
Added to KEVMar 3, 2022
Remediation dueMar 17, 2022
References
- openwall.com/lists/oss-security/2019/09/28/1ExploitMailing List
- openwall.com/lists/oss-security/2019/09/28/2ExploitMailing List
- openwall.com/lists/oss-security/2019/09/28/3Mailing ListThird Party Advisory
- openwall.com/lists/oss-security/2019/09/28/4Mailing ListThird Party Advisory
- bugs.exim.org/show_bug.cgi?id=2449Issue TrackingPatch
- git.exim.org/exim.git/commit/478effbfd9c3cc5a627fc671d4bf94d13670d65fPatch
- lists.exim.org/lurker/message/20190927.032457.c1044d4c.en.htmlVendor Advisory
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EED7HM3MFIBAP5OIMJAFJ35JAJABTVSC/Release Notes
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T3TJW4HPYH3O5HZCWGD6NSHTEBTTAPDC/Release Notes
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UY6HPRW7MR3KBQ5JFHH6OXM7YCZBJCOB/Release Notes
- seclists.org/bugtraq/2019/Sep/60Mailing ListThird Party Advisory
- security.gentoo.org/glsa/202003-47Third Party Advisory
0 recent articles mention this CVE
83
Risk assessment · Critical
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1684 days
- CVSS
- 9.8 CRITICAL
- EPSS (30-day exploit probability)
- 41.6% · top 1% of all CVEs
- Weakness
- CWE-787
- Attack vector
- Network, remotely reachable
- Preconditions
- No privileges and no user interaction
Recommended actions
- 1.Apply updates per vendor instructions.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.