CVE-2019-16928
9.8, critical Known exploitedExim Out-of-bounds Write Vulnerability
- CVSS
- 9.8, critical critical CVSS v3.1
- EPSS, next 30 days
- 42% higher than 98.6% of scored CVEs
- Exploitation
- Confirmed in the wild
- Published
- 27 Sept 20197 years ago
Known exploited
CISA added this to the Known Exploited Vulnerabilities Catalog on 3 Mar 2022. US federal agencies had to remediate by 17 Mar 2022, a deadline that has passed.
Required action. Apply updates per vendor instructions.
Description
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.
Details
- Vendor
- Exim and 3 more
- Product
- Exim
- Weakness
- CWE-787 (opens in a new tab)
- Status
- Analyzed
- Updated
- 17 Jun 2026
- Assigner
- cve@mitre.org
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References 15
Exploit code 2
Patches and fixes 2
Advisories 7
- openwall.com /lists/oss-security/2019/09/28/3 (opens in a new tab)
- openwall.com /lists/oss-security/2019/09/28/4 (opens in a new tab)
- lists.exim.org /lurker/message/20190927.032457.c1044d4c.en.html (opens in a new tab)
- seclists.org /bugtraq/2019/Sep/60 (opens in a new tab)
- security.gentoo.org /glsa/202003-47 (opens in a new tab)
- usn.ubuntu.com /4141-1/ (opens in a new tab)
- debian.org /security/2019/dsa-4536 (opens in a new tab)
Other references 4
- lists.fedoraproject.org /archives/list/package-announce%40lists.fedoraproject.org/message/EED7HM3MFIBAP5OIMJAFJ35JAJABTVSC/ (opens in a new tab)
- lists.fedoraproject.org /archives/list/package-announce%40lists.fedoraproject.org/message/T3TJW4HPYH3O5HZCWGD6NSHTEBTTAPDC/ (opens in a new tab)
- lists.fedoraproject.org /archives/list/package-announce%40lists.fedoraproject.org/message/UY6HPRW7MR3KBQ5JFHH6OXM7YCZBJCOB/ (opens in a new tab)
- cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-16928 (opens in a new tab)
The kind is read from NVD's tags where present and from the shape of the URL otherwise, so treat it as a hint.
Other Exim CVEs
Every Exim CVE we holdSame vendor in what we hold, not a known link between the flaws.
- CVE-2019-10149 Exim Mail Transfer Agent (MTA) Improper Input Validation KEV EPSS 100% 9.8, critical
- CVE-2018-6789 Exim Buffer Overflow Vulnerability KEV EPSS 82% 9.8, critical
- CVE-2010-4344 Exim Heap-Based Buffer Overflow Vulnerability KEV EPSS 72% 9.8, critical
- CVE-2010-4345 Exim Privilege Escalation Vulnerability KEV EPSS 18% 7.8, high
- CVE-2026-94056 Exim before 4.100.1, when Proxy-Protocol is used with an attacker-controlled proxy, allows attackers to read certain uninitialized data… EPSS 0.2% 7.5, high
Beyond this page
Is CVE-2019-16928 in your network?
This page tells you how dangerous CVE-2019-16928 is out there. Whether it sits on one of your devices, only a scan of your own network can tell. That is what our systems do, every day, for the companies we protect.
CVE-2019-16928 is in the CISA catalogue of exploited vulnerabilities: attackers are already exploiting it.
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EXYS7600 OCELOT
Find it before attackers do
Ocelot scans your network on a schedule and reports every vulnerability it finds by its CVE identifier, with its CVSS score and how many of your hosts are affected. A finding like CVE-2019-16928 comes with the devices to patch.
Learn more about EXYS7600 OCELOT -
EXYS7950 KONDRA
Detect it if it's exploited
Until the patch is applied, Kondra monitors your network, events and endpoints in real time. It keeps an inventory of the software installed on every endpoint, and its anomaly detection rules flag what an attacker does once inside.
Learn more about EXYS7950 KONDRA
Assembled from the NVD 2.0 API, the CISA Known Exploited Vulnerabilities Catalog and FIRST EPSS. Scores are as of our last collection on 17 Oct 2026, not the live upstream state.