#VU23600 Input validation error in SpamAssassin - CVE-2019-12420

Vulnerability identifier: #VU23600

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-12420

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
SpamAssassin
Server applications / DLP, anti-spam, sniffers

Vendor: Apache Foundation

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input when parsing multipart email messages. A remote attacker can send a specially crafted email message and consume all available resources on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

SpamAssassin: 3.4.0 - 3.4.2

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External links
https://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@%3Cannounce.apache.org%3E
https://lists.apache.org/thread.html/5ef362d6da12126fafc81443309ca95d872d1bfd011fe4b2699f0fe9@%3Cusers.spamassassin.apache.org%3E
https://lists.apache.org/thread.html/64cf76749956dd08f7d5b86ec9f3321f382cfd7fe717ccd1be940c92@%3Cannounce.spamassassin.apache.org%3E
https://lists.apache.org/thread.html/e3c2367351286b77a74a082e2b66b793cceefa7b6ea9dcd162db4c4b@%3Cdev.spamassassin.apache.org%3E
https://svn.apache.org/repos/asf/spamassassin/branches/3.4/build/announcements/3.4.3.txt

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.