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CVE-2020-35680

HIGH

7.5

CVSS Severity Score

EPSS Score0.0870%

EPSS Percentile44.07th

PublishedDec 24, 2020

Last ModifiedNov 21, 2024

Vulnerability Description

smtpd/lka_filter.c in OpenSMTPD before 6.8.0p1, in certain configurations, allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted pattern of client activity, because the filter state machine does not properly maintain the I/O channel between the SMTP engine and the filters layer.

Affected Platforms (CPE)

📦

Opensmtpd

Opensmtpd

< 6.8.0

📦

Opensmtpd

Opensmtpd

= 6.8.0

📦

Opensmtpd

Opensmtpd

= 6.8.0

💻

Fedoraproject

Fedora

= 32

💻

Fedoraproject

Fedora

= 33

References & Advisories

🔗 https://github.com/openbsd/src/commit/6c3220444ed06b5796dedfd53a0f4becd903c0d1

🔗 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LKTFBQCHGMVPR4IZWHQIYAPM5J3LN3J/

🔗 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TYAYXRV2DM5K4RU7RHCDZSA2UF6VCTRC/

🔗 https://poolp.org/posts/2020-12-24/december-2020-opensmtpd-6.8.0p1-released-fixed-several-bugs-proposed-several-diffs-book-is-on-github/

🔗 https://security.gentoo.org/glsa/202105-12

🔗 https://www.mail-archive.com/misc%40opensmtpd.org/msg05188.html

🔗 https://github.com/openbsd/src/commit/6c3220444ed06b5796dedfd53a0f4becd903c0d1

🔗 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LKTFBQCHGMVPR4IZWHQIYAPM5J3LN3J/

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