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AUSCERT External Security Bulletin Redistribution
ESB-2020.1763
Dovecot -- Multiple vulnerabilities
19 May 2020
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AusCERT Security Bulletin Summary
---------------------------------
Product: dovecot
Publisher: FreeBSD
Operating System: FreeBSD
Impact/Access: Execute Arbitrary Code/Commands -- Remote with User Interaction
Denial of Service -- Remote/Unauthenticated
Resolution: Patch/Upgrade
CVE Names: CVE-2020-10967 CVE-2020-10958 CVE-2020-10957
Reference: ESB-2020.1762
Original Bulletin:
http://www.vuxml.org/freebsd/37d106a8-15a4-483e-8247-fcb68b16eaf8.html
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Dovecot -- Multiple vulnerabilities
Affected packages
dovecot < 2.3.10.1
Details
VuXML ID 37d106a8-15a4-483e-8247-fcb68b16eaf8
Discovery 2020-04-02
Entry 2020-05-18
Aki Tuomi reports:
Vulnerability Details: Sending malformed NOOP command causes crash in
submission, submission-login or lmtp service. Risk: Remote attacker can
keep submission-login service down, causing denial of service attack. For
lmtp the risk is neglible, as lmtp is usually behind a trusted MTA. Steps
to reproduce: Send ``NOOP EE"FY`` to submission port, or similarly
malformed command.
Vulnerability Details: Sending command followed by sufficient number of
newlines triggers a use-after-free bug that might crash submission-login,
submission or lmtp service. Risk: Remote attacker can keep submission-login
service down, causing denial of service attack. For lmtp the risk is
neglible, as lmtp is usually behind a trusted MTA. Steps to reproduce: This
can be currently reproduced with ASAN or Valgrind. Reliable way to crash
has not yet been discovered.
Vulnerability Details: Sending mail with empty quoted localpart causes
submission or lmtp component to crash. Risk: Malicious actor can cause
denial of service to mail delivery by repeatedly sending mails with bad
sender or recipient address. Steps to reproduce: Send mail with envelope
sender or recipient as <""@example.org>. Workaround: For submission there
is no workaround, but triggering the bug requires valid credentials. For
lmtp, one can implement sufficient filtering on MTA level to prevent mails
with such addresses from ending up in LMTP delivery.
[source]
References
CVE Name CVE-2020-10957
CVE Name CVE-2020-10958
CVE Name CVE-2020-10967
URL https://dovecot.org/pipermail/dovecot-news/2020-May/000438.html
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