CVE-2017-15705

Description

A denial of service vulnerability was identified that exists in Apache SpamAssassin before 3.4.2. The vulnerability arises with certain unclosed tags in emails that cause markup to be handled incorrectly leading to scan timeouts. In Apache SpamAssassin, using HTML::Parser, we setup an object and hook into the begin and end tag event handlers In both cases, the open event is immediately followed by a close event - even if the tag *does not* close in the HTML being parsed. Because of this, we are missing the text event to deal with the object normally. This can cause carefully crafted emails that might take more scan time than expected leading to a Denial of Service. The issue is possibly a bug or design decision in HTML::Parser that specifically impacts the way Apache SpamAssassin uses the module with poorly formed html. The exploit has been seen in the wild but not believed to have been purposefully part of a Denial of Service attempt. We are concerned that there may be attempts to abuse the vulnerability in the future.

Risk Information

Base Score

5.3

MODERATE

Vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS Score

Exploitation Probability

1.771

Associated Vulnerability

Vulnerability	OS Platform
Perl-based spam filter using text analysis (USN-3811-1) spamassassin_3.4.2-0ubuntu0.14.04.1_all.deb	Linux
Perl-based spam filter using text analysis (USN-3811-1) spamassassin_3.4.2-0ubuntu0.16.04.1_all.deb	Linux
Perl-based spam filter using text analysis (USN-3811-1) spamassassin_3.4.2-0ubuntu0.18.04.1_all.deb	Linux
Spamassassin security update (CESA-2018:2916) spamassassin-3.4.0-4.el7_5.x86_64.rpm	Linux
(RHSA-2018:2916) spamassassin security update spamassassin-3.4.0-4.el7_5.x86_64.rpm	Linux
Spamassassin update (ELSA-2018-2916) spamassassin-3.4.0-4.el7_5.x86_64.rpm	Linux

Patch Details

No records found

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234