From: Jeremy Harris Date: Mon, 2 Oct 2023 12:24:29 +0000 (+0100) Subject: Merge branch 'exim-4.96+security' X-Git-Tag: exim-4.97-RC2~6 X-Git-Url: https://git.exim.org/exim.git/commitdiff_plain/18eacc1185bea956bd9c793ab34e582c08941799 Merge branch 'exim-4.96+security' --- 18eacc1185bea956bd9c793ab34e582c08941799 diff --cc doc/doc-txt/ChangeLog index efa79de22,8c5b7fd9c..a78ec386f --- a/doc/doc-txt/ChangeLog +++ b/doc/doc-txt/ChangeLog @@@ -2,197 -2,23 +2,209 @@@ This document describes *changes* to pr affect Exim's operation, with an unchanged configuration file. For new options, and new features, see the NewStuff file next to this ChangeLog. -Exim version 4.96.1 -------------------- +Exim version 4.97 +----------------- + +JH/01 The hosts_connection_nolog main option now also controls "no MAIL in + SMTP connection" log lines. + +JH/02 Option default value updates: + - queue_fast_ramp (main) true (was false) + - remote_max_parallel (main) 4 (was 2) + +JH/03 Cache static regex pattern compilations, for use by ACLs. + +JH/04 Bug 2903: avoid exit on an attempt to rewrite a malformed address. + Make the rewrite never match and keep the logging. Trust the + admin to be using verify=header-syntax (to actually reject the message). + +JH/05 Follow symlinks for placing a watch on TLS creds files. This means + (under Linux) we watch the dir containing the final file; previously + it would be the dir with the first symlink. We still do not monitor + the entire path. + +JH/06 Check for bad chars in rDNS for sender_host_name. The OpenBSD (at least) + dn_expand() is happy to pass them through. + +JH/07 OpenSSL Fix auto-reload of changed server OCSP proof. Previously, if + the file with the proof had an unchanged name, the new proof(s) were + loaded on top of the old ones (and nover used; the old ones were stapled). + +JH/08 Bug 2915: Fix use-after-free for $regex variables. Previously when + more than one message arrived in a single connection a reference from + the earlier message could be re-used. Often a sigsegv resulted. + These variables were introduced in Exim 4.87. + Debug help from Graeme Fowler. + +JH/09 Fix ${filter } for conditions that modify $value. Previously the + modified version would be used in construction the result, and a memory + error would occur. + +JH/10 GnuTLS: fix for (IOT?) clients offering no TLS extensions at all. + Find and fix by Jasen Betts. + +JH/11 OpenSSL: fix for ancient clients needing TLS support for versions earlier + than TLSv1,2, Previously, more-recent versions of OpenSSL were permitting + the systemwide configuration to override the Exim config. + +HS/01 Bug 2728: Introduce EDITME option "DMARC_API" to work around incompatible + API changes in libopendmarc. + +JH/12 Bug 2930: Fix daemon startup. When started from any process apart from + pid 1, in the normal "background daemon" mode, having to drop process- + group leadership also lost track of needing to create listener sockets. + +JH/13 Bug 2929: Fix using $recipients after ${run...}. A change made for 4.96 + resulted in the variable appearing empty. Find and fix by Ruben Jenster. + +JH/14 Bug 2933: Fix regex substring match variables for null matches. Since 4.96 + a capture group which obtained no text (eg. "(abc)*" matching zero + occurrences) could cause a segfault if the corresponding $ was + expanded. + +JH/15 Fix argument parsing for ${run } expansion. Previously, when an argument + included a close-brace character (eg. it itself used an expansion) an + error occurred. + +JH/16 Move running the smtp connect ACL to before, for TLS-on-connect ports, + starting TLS. Previously it was after, meaning that attackers on such + ports had to be screened using the host_reject_connection main config + option. The new sequence aligns better with the STARTTLS behaviour, and + permits defences against crypto-processing load attacks, even though it + is strictly an incompatible change. + Also, avoid sending any SMTP fail response for either the connect ACL + or host_reject_connection, for TLS-on-connect ports. + +JH/17 Permit the ACL "encrypted" condition to be used in a HELO/EHLO ACL, + Previously this was not permitted, but it makes reasonable sense. + While there, restore a restriction on using it from a connect ACL; given + the change JH/16 it could only return false (and before 4.91 was not + permitted). + +JH/18 Fix a fencepost error in logging. Previously (since 4.92) when a log line + was exactly sized compared to the log buffer, a crash occurred with the + misleading message "bad memory reference; pool not found". + Found and traced by Jasen Betts. + +JH/19 Bug 2911: Fix a recursion in DNS lookups. Previously, if the main option + dns_again_means_nonexist included an element causing a DNS lookup which + itself returned DNS_AGAIN, unbounded recursion occurred. Possible results + included (though probably not limited to) a process crash from stack + memory limit, or from excessive open files. Replace this with a paniclog + whine (as this is likely a configuration error), and returning + DNS_NOMATCH. + +JH/20 Bug 2954: (OpenSSL) Fix setting of explicit EC curve/group. Previously + this always failed, probably leading to the usual downgrade to in-clear + connections. + +JH/21 Fix TLSA lookups. Previously dns_again_means_nonexist would affect + SERVFAIL results, which breaks the downgrade resistance of DANE. Change + to not checking that list for these lookups. + +JH/22 Bug 2434: Add connection-elapsed "D=" element to more connection + closure log lines. + +JH/23 Fix crash in string expansions. Previously, if an empty variable was + immediately followed by an expansion operator, a null-indirection read + was done, killing the process. + +JH/24 Bug 2997: When built with EXPERIMENTAL_DSN_INFO, bounce messages can + include an SMTP response string which is longer than that supported + by the delivering transport. Alleviate by wrapping such lines before + column 80. + +JH/25 Bug 2827: Restrict size of References: header in bounce messages to 998 + chars (RFC limit). Previously a limit of 12 items was made, which with + a not-impossible References: in the message being bounced could still + be over-large and get stopped in the transport. + +JH/26 For a ${readsocket } in TLS mode, send a TLS Close Alert before the TCP + close. Previously a bare socket close was done. + +JH/27 Fix ${srs_encode ..}. Previously it would give a bad result for one day + every 1024 days. + +JH/28 Bug 2996: Fix a crash in the smtp transport. When finding that the + message being considered for delivery was already being handled by + another process, and having an SMTP connection already open, the function + to close it tried to use an uninitialized variable. This would afftect + high-volume sites more, especially when running mailing-list-style loads. + Pollution of logs was the major effect, as the other process delivered + the message. Found and partly investigated by Graeme Fowler. + +JH/29 Change format of the internal ID used for message identification. The old + version only supported 31 bits for a PID element; the new 64 (on systems + which can use Base-62 encoding, which is all currently supported ones + but not Darwin (MacOS) or Cygwin, which have case-insensitive filesystems + and must use Base-36). The new ID is 23 characters rather than 16, and is + visible in various places - notably logs, message headers, and spool file + names. Various of the ancillary utilities also have to know the format. + As well as the expanded PID portion, the sub-second part of the time + recorded in the ID is expanded to support finer precision. Theoretically + this permits a receive rate from a single comms channel of better than the + previous 2000/sec. + The major timestamp part of the ID is not changed; at 6 characters it is + usable until about year 3700. + Updating from previously releases is fully supported: old-format spool + files are still usable, and the utilities support both formats. New + message will use the new format. The one hints-DB file type which uses + message-IDs (the transport wait- DB) will be discarded if an old-format ID + is seen; new ones will be built with only new-format IDs. + Optionally, a utility can be used to convert spool files from old to new, + but this is only an efficiency measure not a requirement for operation + Downgrading from new to old requires running a provided utility, having + first stopped all operations. This will convert any spool files from new + back to old (losing time-precision and PID information) and remove any + wait- hints databases. + +JH/30 Bug 3006: Fix handling of JSON strings having embedded commas. Previously + we treated them as item separators when parsing for a list item, but they + need to be protected by the doublequotes. While there, add handling for + backslashes. + +JH/31 Bug 2998: Fix ${utf8clean:...} to disallow UTF-16 surrogate codepoints. + Found and fixed by Jasen Betts. No testcase for this as my usual text + editor insists on emitting only valid UTF-8. + +JH/32 Fix "tls_dhparam = none" under GnuTLS. At least with 3.7.9 this gave + a null-indirection SIGSEGV for the receive process. + +JH/33 Fix free for live variable $value created by a ${run ...} expansion during + -bh use. Internal checking would spot this and take a panic. + +JH/34 Bug 3013: Fix use of $recipients within arguments for ${run...}. + In 4.96 this would expand to empty. + +JH/35 Bug 3014: GnuTLS: fix expiry date for an auto-generated server + certificate. Find and fix by Andreas Metzler. + +JH/36 Add ARC info to DMARC hostory records. + +JH/37 Bug 3016: Avoid sending DSN when message was accepted under fakereject + or fakedefer. Previously the sender could discover that the message + had in fact been accepted. + +JH/38 Taint-track intermediate values from the peer in multi-stage authentation + sequences. Previously the input was not noted as being tainted; notably + this resulted in behaviour of LOGIN vs. PLAIN being inconsistent under + bad coding of authenticators. -This is a security release. +JH/39 Bug 3023: Fix crash induced by some combinations of zero-length strings + and ${tr...}. Found and diagnosed by Heiko Schlichting. -JH/01 Bug 2999: Fix a possible OOB write in the external authenticator, which ++JH/40 Bug 2999: Fix a possible OOB write in the external authenticator, which + could be triggered by externally-supplied input. Found by Trend Micro. + CVE-2023-42115 + -JH/02 Bug 3000: Fix a possible OOB write in the SPA authenticator, which could ++JH/41 Bug 3000: Fix a possible OOB write in the SPA authenticator, which could + be triggered by externally-controlled input. Found by Trend Micro. + CVE-2023-42116 + -JH/03 Bug 3001: Fix a possible OOB read in the SPA authenticator, which could ++JH/42 Bug 3001: Fix a possible OOB read in the SPA authenticator, which could + be triggered by externally-controlled input. Found by Trend Micro. + CVE-2023-42114 + Exim version 4.96 -----------------