1 Security fix for CVE-2016-1531
2 ==============================
4 All installations having Exim set-uid root and using 'perl_startup' are
5 vulnerable to a local privilege escalation. Any user who can start an
6 instance of Exim (and this is normally *any* user) can gain root
9 The official fix is in Exim release 4.86.2. (tagged as exim-4_86_2)
11 For your convenience we released 4.85.2 (tagged as exim-4_85_2)
12 4.84.2 (tagged as exim-4_84_2)
14 To support package maintainers on older systems we maintain (on a best
15 effort basis) GIT branches with backported patches for older releases:
17 exim-4_80_1+CVE-2016-1531
18 exim-4_82_1+CVE-2016-1531
20 (We didn't assign GIT tags, to indicate that's nothing real official.)
26 We had to introduce two new configuration options:
31 Both options are empty per default. That is, Exim cleans the complete
32 environment on startup. This affects Exim itself and any subprocesses,
33 as transports, that may call other programs via some alias mechanisms,
34 as routers (queryprogram), lookups, and so on.
36 ** THIS MAY BREAK your existing installation **
38 If both options are not used in the configuration, Exim issues a warning
39 on startup. This warning disappears if at least one of these options is
40 used (even if set to an empty value).
42 keep_environment should contain a list of trusted environment variables.
43 (Do you trust PATH?). This may be a list of names and REs.
45 keep_environment = ^LDAP_ : FOO_PATH
47 To add (or override) variables, you can use add_environment:
49 add_environment = <; PATH=/sbin:/usr/sbin
55 Now Exim changes its working directory to / right after startup,
56 even before reading its configuration. (Later Exim changes its working
57 directory to $spool_directory, as usual.)
59 Exim only accepts an absolute configuration file path now, when using
63 Thank you for your understanding.
65 [Heiko Schlittermann <hs@schlittermann.de>]