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 4.96.2
+-------------------
+
+JH/01 Bug 3033: Harden dnsdb lookups against crafted DNS responses.
+ CVE-2023-42219
+
+HS/01 Fix string_is_ip_address() CVE-2023-42117 (Bug 3031)
+
+
Exim version 4.96.1
-------------------
be triggered by externally-controlled input. Found by Trend Micro.
CVE-2023-42114
-
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).
-Exim version 4.next
--------------------
-
-HS/01 Fix string_is_ip_address() CVE-2023-42117 (Bug 3031)
-
-
-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<n> 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 $<n> 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
- iteslf 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.
-
-JH/39 Bug 3023: Fix crash induced by some combinations of zero-length strings
- and ${tr...}. Found and diagnosed by Heiko Schlichting.
-
-JH/40 Support list of dkim results in the dkim_status ACL condition, making
- it more usable in the data ACL.
-
-
Exim version 4.96
-----------------