Bugzilla – Bug 1188875
VUL-0: CVE-2021-36386: fetchmail: DoS or information disclosure in some configurations
Last modified: 2021-12-17 14:18:47 UTC
CVE-2021-36386 ANNOUNCE: fetchmail <= 6.4.19 security announcement 2021-01 (CVE-2021-36386) - fetchmail 6.4.20 released. DoS or information disclosure in some configurations From: Matthias Andree Date: Wed, 28 Jul 2021 23:27:00 +0200 Greetings, I have announced fetchmail 6.4.20 today, which fixes the issue shown in the security announcement below. fetchmail 6.4.20 is available from. The source archive is available at: Detached GnuPG signatures for the respective tarballs are at: SHA256 hash values for the tarballs: SHA256(fetchmail-6.4.20.tar.lz)= 497973353c0538216e7d7f2289a21d9acc5edd78f06d7ec008001f4f19e91b11 SHA256(fetchmail-6.4.20.tar.xz)= c82141ae2e8f0039ceb0c5c2eda43c5e93ad0bf7f9c6bb628092b3be74386176 ------------------------------------------------------------------------------------------------ fetchmail-SA-2021-01: DoS or information disclosure logging long messages Topics: fetchmail denial of service or information disclosure when logging long messages Author: Matthias Andree Version: 1.1 Announced: 2021-07-28 Type: missing variable initialization can cause read from bad memory locations Impact: fetchmail logs random information, or segfaults and aborts, stalling inbound mail Danger: low Acknowledgment: Christian Herdtweck, Intra2net AG, Tübingen, Germany for analysis and report and a patch suggestion CVE Name: CVE-2021-36386 URL: https://www.fetchmail.info/fetchmail-SA-2021-01.txt Project URL: https://www.fetchmail.info/ Affects: - fetchmail releases up to and including 6.4.19 Not affected: - fetchmail releases 6.4.20 and newer Corrected in: c546c829 Git commit hash 2021-07-28 fetchmail 6.4.20 release tarball 0. Release history ================== 2021-07-07 initial report to maintainer 2021-07-28 1.0 release 2021-07-28 1.1 update Git commit hash with correction 1. Background ============= fetchmail is a software package to retrieve mail from remote POP3, IMAP, ETRN or ODMR servers and forward it to local SMTP, LMTP servers or message delivery agents. fetchmail supports SSL and TLS security layers through the OpenSSL library, if enabled at compile time and if also enabled at run time, in both SSL/TLS-wrapped mode on dedicated ports as well as in-band-negotiated "STARTTLS" and "STLS" modes through the regular protocol ports. 2. Problem description and Impact ================================= Fetchmail has long had support to assemble log/error messages that are generated piecemeal, and takes care to reallocate the output buffer as needed. In the reallocation case, i. e. when long log messages are assembled that can stem from very long headers, and on systems that have a varargs.h/stdarg.h interface (all modern systems), fetchmail's code would fail to reinitialize the va_list argument to vsnprintf. The exact effects depend on the verbose mode (how many -v are given) of fetchmail, computer architecture, compiler, operating system and configuration. On some systems, the code just works without ill effects, some systems log a garbage message (potentially disclosing sensitive information), some systems log literally "(null)", some systems trigger SIGSEGV (signal #11), which crashes fetchmail, causing a denial of service on fetchmail's end. 3. Solution =========== Install fetchmail 6.4.20 or newer. The fetchmail source code is available from . Distributors are encouraged to review the NEWS file and move forward to 6.4.20, rather than backport individual security fixes, because doing so routinely misses other fixes crucial to fetchmail's proper operation, for which no security announcements are issued, or documentation, or translation updates. Fetchmail 6.4.X releases have been made with a focus on unchanged user and program interfaces so as to avoid disruptions when upgrading from 6.3.Z or 6.4.X to 6.4.Y with Y > X. Care was taken to not change the interface incompatibly. A. Copyright, License and Non-Warranty ====================================== (C) Copyright 2021 by Matthias Andree, . Some rights reserved. fetchmail-SA-2021-01 © 2021 by Matthias Andree is licensed under CC BY-ND 4.0. To view a copy of this license, visit http://creativecommons.org/licenses/by-nd/4.0/ THIS WORK IS PROVIDED FREE OF CHARGE AND WITHOUT ANY WARRANTIES. Use the information herein at your own risk. END of fetchmail-SA-2021-01 References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-36386 http://seclists.org/oss-sec/2021/q3/56
commit: https://gitlab.com/fetchmail/fetchmail/-/commit/c546c8299243a10a7b85c638e0e61396ecd5d8b5
tracking these as affected: - SUSE:SLE-11:Update/fetchmail - SUSE:SLE-12:Update/fetchmail - SUSE:SLE-15:Update/fetchmail and Factory
Factory update to 6.4.20: https://build.opensuse.org/request/show/909104
For SLE-11_Update, the follosing commit is also required for back-port: https://gitlab.com/fetchmail/fetchmail/-/commit/414a380974f78d0bb62ca953398bf1f54b28a58d
Created attachment 851400 [details] Back-ported patch for SLE-11_Update Contains also the commit mentioned in c#4.
Submitted also to SLE-11_Update in sr#247378.
SUSE-SU-2021:2771-1: An update that solves one vulnerability and has three fixes is now available. Category: security (moderate) Bug References: 1033081,1182807,1188034,1188875 CVE References: CVE-2021-36386 JIRA References: Sources used: SUSE OpenStack Cloud Crowbar 9 (src): fetchmail-6.3.26-13.12.1 SUSE OpenStack Cloud 9 (src): fetchmail-6.3.26-13.12.1 SUSE OpenStack Cloud 8 (src): fetchmail-6.3.26-13.12.1 SUSE Linux Enterprise Server for SAP 12-SP4 (src): fetchmail-6.3.26-13.12.1 SUSE Linux Enterprise Server for SAP 12-SP3 (src): fetchmail-6.3.26-13.12.1 SUSE Linux Enterprise Server 12-SP5 (src): fetchmail-6.3.26-13.12.1 SUSE Linux Enterprise Server 12-SP4-LTSS (src): fetchmail-6.3.26-13.12.1 SUSE Linux Enterprise Server 12-SP3-LTSS (src): fetchmail-6.3.26-13.12.1 SUSE Linux Enterprise Server 12-SP3-BCL (src): fetchmail-6.3.26-13.12.1 SUSE Linux Enterprise Server 12-SP2-BCL (src): fetchmail-6.3.26-13.12.1 NOTE: This line indicates an update has been released for the listed product(s). At times this might be only a partial fix. If you have questions please reach out to maintenance coordination.
# maintenance_jira_update_notice SUSE-SU-2021:2791-1: An update that solves one vulnerability and has one errata is now available. Category: security (moderate) Bug References: 1188034,1188875 CVE References: CVE-2021-36386 JIRA References: Sources used: SUSE Manager Server 4.0 (src): fetchmail-6.3.26-20.14.1 SUSE Manager Retail Branch Server 4.0 (src): fetchmail-6.3.26-20.14.1 SUSE Manager Proxy 4.0 (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Server for SAP 15-SP1 (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Server for SAP 15 (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Server 15-SP1-LTSS (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Server 15-SP1-BCL (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Server 15-LTSS (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Module for Desktop Applications 15-SP3 (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Module for Desktop Applications 15-SP2 (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Module for Basesystem 15-SP3 (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise Module for Basesystem 15-SP2 (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise High Performance Computing 15-SP1-LTSS (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise High Performance Computing 15-SP1-ESPOS (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise High Performance Computing 15-LTSS (src): fetchmail-6.3.26-20.14.1 SUSE Linux Enterprise High Performance Computing 15-ESPOS (src): fetchmail-6.3.26-20.14.1 SUSE Enterprise Storage 6 (src): fetchmail-6.3.26-20.14.1 SUSE CaaS Platform 4.0 (src): fetchmail-6.3.26-20.14.1 NOTE: This line indicates an update has been released for the listed product(s). At times this might be only a partial fix. If you have questions please reach out to maintenance coordination.
# maintenance_jira_update_notice openSUSE-SU-2021:2791-1: An update that solves one vulnerability and has one errata is now available. Category: security (moderate) Bug References: 1188034,1188875 CVE References: CVE-2021-36386 JIRA References: Sources used: openSUSE Leap 15.3 (src): fetchmail-6.3.26-20.14.1
# maintenance_jira_update_notice openSUSE-SU-2021:1183-1: An update that solves one vulnerability and has one errata is now available. Category: security (moderate) Bug References: 1188034,1188875 CVE References: CVE-2021-36386 JIRA References: Sources used: openSUSE Leap 15.2 (src): fetchmail-6.3.26-lp152.6.6.1
openSUSE-SU-2021:4018-1: An update that solves two vulnerabilities, contains three features and has four fixes is now available. Category: security (moderate) Bug References: 1152964,1174075,1181400,1188875,1190069,1190896 CVE References: CVE-2021-36386,CVE-2021-39272 JIRA References: SLE-17903,SLE-18059,SLE-18159 Sources used: openSUSE Leap 15.3 (src): fetchmail-6.4.22-20.20.1
SUSE-SU-2021:4018-1: An update that solves two vulnerabilities, contains three features and has four fixes is now available. Category: security (moderate) Bug References: 1152964,1174075,1181400,1188875,1190069,1190896 CVE References: CVE-2021-36386,CVE-2021-39272 JIRA References: SLE-17903,SLE-18059,SLE-18159 Sources used: SUSE Linux Enterprise Server for SAP 15-SP1 (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise Server for SAP 15 (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise Server 15-SP1-LTSS (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise Server 15-SP1-BCL (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise Server 15-LTSS (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise Module for Desktop Applications 15-SP3 (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise Module for Desktop Applications 15-SP2 (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise Module for Basesystem 15-SP3 (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise Module for Basesystem 15-SP2 (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise High Performance Computing 15-SP1-LTSS (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise High Performance Computing 15-SP1-ESPOS (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise High Performance Computing 15-LTSS (src): fetchmail-6.4.22-20.20.1 SUSE Linux Enterprise High Performance Computing 15-ESPOS (src): fetchmail-6.4.22-20.20.1 SUSE Enterprise Storage 6 (src): fetchmail-6.4.22-20.20.1 SUSE CaaS Platform 4.0 (src): fetchmail-6.4.22-20.20.1 NOTE: This line indicates an update has been released for the listed product(s). At times this might be only a partial fix. If you have questions please reach out to maintenance coordination.
openSUSE-SU-2021:1591-1: An update that solves two vulnerabilities, contains three features and has four fixes is now available. Category: security (moderate) Bug References: 1152964,1174075,1181400,1188875,1190069,1190896 CVE References: CVE-2021-36386,CVE-2021-39272 JIRA References: SLE-17903,SLE-18059,SLE-18159 Sources used: openSUSE Leap 15.2 (src): fetchmail-6.4.22-lp152.6.12.1