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 4.95
+Exim version 4.98
+-----------------
+
+JH/01 Support list of dkim results in the dkim_status ACL condition, making
+ it more usable in the data ACL.
+
+JH/02 Bug 3040: Handle error on close of the spool data file during reception.
+ Previously This was only logged, on the assumption that errors would be
+ seen for a previous fflush(). However, a fuse filesystem has been
+ reported as showing this an error for the fclose(). The spool is now in
+ an uncertain state, and we have logged and responded acceptance. Change
+ this to respond with a temp-reject, wipe spoolfiles, and log the error
+ detail.
+
+JH/03 Bug 3030: Fix handling of DNS servfail respons for DANE TLSA. When hit
+ during a recipient verify callout, a QUIT command was attempted on the
+ now-closed callout channel, causing a paniclog entry.
+
+JH/04 Bug 3039: Fix handling of of an empty log_reject_target, with
+ a connection_reject log_selector, under tls_on_connect. Previously
+ with this combination, when the connect ACL rejected, a spurious
+ paniclog entry was made.
+JH/04 Fix TLS resumption for TLS-on-connect. This was broken by the advent
+ of loadbalancer-detection for resumption, in 4.96 - which tries to
+ use the EHLO response. SMTPS does not have one at the time it is starting
+ TLS. Change the default for the smtp transport host_name_extract option
+ to be a static string, for TLS-on-connect cases; meaning that resumption
+ will always be attempted (unless deliberately overriden).
+
+
+
+Exim version 4.97
-----------------
-JH/01 Move the wait-for-next-tick (needed for unique messmage IDs) from
+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
+ 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.
+
+JH/39 Bug 3023: Fix crash induced by some combinations of zero-length strings
+ and ${tr...}. Found and diagnosed by Heiko Schlichting.
+
+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/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/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
+
+JH/43 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/44 Bug 3033: Harden dnsdb lookups against crafted DNS responses.
+ CVE-2023-42219
+
+HS/02 Fix string_is_ip_address() CVE-2023-42117 (Bug 3031)
+
+
+Exim version 4.96
+-----------------
+
+JH/01 Move the wait-for-next-tick (needed for unique message IDs) from
after reception to before a subsequent reception. This should
mean slightly faster delivery, and also confirmation of reception
to senders.
connection was never replaced for subsequent connections. Found by
Wakko Warner.
+JH/12 Bug 2838: Fix for i32lp64 hard-align platforms. Found for SPARC Linux,
+ though only once PCRE2 was introduced: the memory accounting used under
+ debug offset allocations by an int, giving a hard trap in early startup.
+ Change to using a size_t. Debug and fix by John Paul Adrian Glaubitz.
+
+JH/13 Bug 2845: Fix handling of tls_require_ciphers for OpenSSL when a value
+ with underbars is given. The write-protection of configuration introduced
+ in 4.95 trapped when normalisation was applied to an option not needing
+ expansion action.
+
+JH/14 Bug 1895: TLS: Deprecate RFC 5114 Diffie-Hellman parameters.
+
+JH/15 Fix a resource leak in *BSD. An off-by-one error resulted in the daemon
+ failing to close the certificates directory, every hour or any time it
+ was touched.
+
+JH/16 Debugging initiated by an ACL control now continues through into routing
+ and transport processes. Previously debugging stopped any time Exim
+ re-execs, or for processing a queued message.
+
+JH/17 The "expand" debug selector now gives more detail, specifically on the
+ result of expansion operators and items.
+
+JH/18 Bug 2751: Fix include_directory in redirect routers. Previously a
+ bad comparison between the option value and the name of the file to
+ be included was done, and a mismatch was wrongly identified.
+ 4.88 to 4.95 are affected.
+
+JH/19 Support for Berkeley DB versions 1 and 2 is withdrawn.
+
+JH/20 When built with NDBM for hints DB's check for nonexistence of a name
+ supplied as the db file-pair basename. Previously, if a directory
+ path was given, for example via the autoreply "once" option, the DB
+ file.pag and file.dir files would be created in that directory's
+ parent.
+
+JH/21 Remove the "allow_insecure_tainted_data" main config option and the
+ "taint" log_selector. These were previously deprecated.
+
+JH/22 Fix static address-list lookups to properly return the matched item.
+ Previously only the domain part was returned.
+
+JH/23 Bug 2864: FreeBSD: fix transport hang after 4xx/5xx response. Previously
+ the call into OpenSSL to send a TLS Close was being repeated; this
+ resulted in the library waiting for the peer's Close. If that was never
+ sent we waited forever. Fix by tracking send calls.
+
+JH/24 The ${run} expansion item now expands its command string elements after
+ splitting. Previously it was before; the new ordering makes handling
+ zero-length arguments simpler. The old ordering can be obtained by
+ appending a new option "preexpand", after a comma, to the "run".
+
+JH/25 Taint-check exec arguments for transport-initiated external processes.
+ Previously, tainted values could be used. This affects "pipe", "lmtp" and
+ "queryprogram" transport, transport-filter, and ETRN commands.
+ The ${run} expansion is also affected: in "preexpand" mode no part of
+ the command line may be tainted, in default mode the executable name
+ may not be tainted.
+
+JH/26 Fix CHUNKING on a continued-transport. Previously the usabliility of
+ the the facility was not passed across execs, and only the first message
+ passed over a connection could use BDAT; any further ones using DATA.
+
+JH/27 Support the PIPECONNECT facility in the smtp transport when the helo_data
+ uses $sending_ip_address and an interface is specified.
+ Previously any use of the local address in the EHLO name disabled
+ PIPECONNECT, the common case being to use the rDNS of it.
+
+JH/28 OpenSSL: fix transport-required OCSP stapling verification under session
+ resumption. Previously verify failed because no certificate status is
+ passed on the wire for the restarted session. Fix by using the recorded
+ ocsp status of the stored session for the new connection.
+
+JH/29 TLS resumption: the key for session lookup in the client now includes
+ more info that a server could potentially use in configuring a TLS
+ session, avoiding oferring mismatching sessions to such a server.
+ Previously only the server IP was used.
+
+JH/30 Fix string_copyn() for limit greater than actual string length.
+ Previously the copied amount was the limit, which could result in a
+ overlapping memcpy for newly allocated destination soon after a
+ source string shorter than the limit. Found/investigated by KM.
+
+JH/31 Bug 2886: GnuTLS: Do not free the cached creds on transport connection
+ close; it may be needed for a subsequent connection. This caused a
+ SEGV on primary-MX defer. Found/investigated by Gedalya & Andreas.
+
+JH/32 Fix CHUNKING for a second message on a connection when the first was
+ rejected. Previously we did not reset the chunking-offered state, and
+ erroneously rejected the BDAT command. Investigation help from
+ Jesse Hathaway.
+
+JH/33 Fis ${srs_encode ...} to handle an empty sender address, now returning
+ an empty address. Previously the expansion returned an error.
+
+HS/01 Bug 2855: Handle a v4mapped sender address given us by a frontending
+ proxy. Previously these were misparsed, leading to paniclog entries.
+
Exim version 4.95
-----------------
to do ARC verification. The Authentication-Results: header line added
by the configuration then had no ARC item.
+JH/48 Bug 2784: fix shutdown=no in the ${readsocket) expansion item. Previously
+ an incorrect mode was used for reading the result, resulting in it being
+ ignored.
+
Exim version 4.92
-----------------