CVE-2019-12420

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 7.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-12-12 · updated 2026-06-17
Weakness: CWE-400

Description

In Apache SpamAssassin before 3.4.3, a message can be crafted in a way to use excessive resources. Upgrading to SA 3.4.3 as soon as possible is the recommended fix but details will not be shared publicly.

Affected products

Apache Software Foundation Apache SpamAssassin: before 3.4.3 — fixed in 3.4.3
Debian Linux: 8.0, 9.0, 10.0

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache SpamAssassin 3.4.3. Check the vendor advisory for mitigations.

References

http://www.openwall.com/lists/oss-security/2019/12/12/2
https://bz.apache.org/SpamAssassin/show_bug.cgi?id=7747
https://lists.apache.org/thread.html/5863d6c42fc9595a29566732f12348cde0ca0e41bda91695c62041de%40%3Cannounce.apache.org%3E
https://lists.apache.org/thread.html/5ef362d6da12126fafc81443309ca95d872d1bfd011fe4b2699f0fe9%40%3Cusers.spamassassin.apache.org%3E
https://lists.apache.org/thread.html/64cf76749956dd08f7d5b86ec9f3321f382cfd7fe717ccd1be940c92%40%3Cannounce.spamassassin.apache.org%3E
https://lists.apache.org/thread.html/e3c2367351286b77a74a082e2b66b793cceefa7b6ea9dcd162db4c4b%40%3Cdev.spamassassin.apache.org%3E
https://lists.apache.org/thread.html/r2578c486552637bfedbe624940cc60d6463bd90044c887bdebb75e74%40%3Cusers.spamassassin.apache.org%3E
https://lists.apache.org/thread.html/r3d32ebf97b1245b8237763444e911c4595d2ad5e34a1641840d8146f%40%3Cusers.spamassassin.apache.org%3E
https://lists.debian.org/debian-lts-announce/2019/12/msg00019.html
https://seclists.org/bugtraq/2019/Dec/27
https://svn.apache.org/repos/asf/spamassassin/branches/3.4/build/announcements/3.4.3.txt
https://usn.ubuntu.com/4237-1/

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