diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/bugs/Symlinked_srcdir_requires_trailing_slash.mdwn | 17 | ||||
| -rw-r--r-- | doc/security.mdwn | 30 |
2 files changed, 46 insertions, 1 deletions
diff --git a/doc/bugs/Symlinked_srcdir_requires_trailing_slash.mdwn b/doc/bugs/Symlinked_srcdir_requires_trailing_slash.mdwn index 0310c17f3..cd74c2496 100644 --- a/doc/bugs/Symlinked_srcdir_requires_trailing_slash.mdwn +++ b/doc/bugs/Symlinked_srcdir_requires_trailing_slash.mdwn @@ -63,4 +63,19 @@ My output: scanning index.mdwn rendering index.mdwn -Note that index.mdwn was only rendered when srcdir had a trailing slash.
\ No newline at end of file +Note that index.mdwn was only rendered when srcdir had a trailing slash. + +> There are potential [[security]] issues with ikiwiki following a symlink, +> even if it's just a symlink at the top level of the srcdir. +> Consider ikiwiki.info's own setup, where the srcdir is ikiwiki/doc, +> checked out of revision control. A malicious committer could convert +> ikiwiki/doc into a symlink to /etc, then ikiwiki would happily publish +> all of /etc to the web. +> +> This kind of attack is why ikiwiki does not let File::Find follow +> symlinks when scanning the srcdir. By appending the slash, you're +> actually bypassing that check. Ikiwiki should not let you set +> up a potentially insecure configuration like that. More discussion of +> this hole [[here|security#index29h2]], and I've had to release +> a version of ikiwiki that explicitly checks for that, and fails to work. +> Sorry, but security trumps convenience. [[done]] --[[Joey]] diff --git a/doc/security.mdwn b/doc/security.mdwn index b1e8d03f6..a1c2120ce 100644 --- a/doc/security.mdwn +++ b/doc/security.mdwn @@ -315,3 +315,33 @@ This hole was discovered on 21 March 2007 and fixed the same day with the release of ikiwiki 1.47. A fix was also backported to Debian etch, as version 1.33.3. I recommend upgrading to one of these versions if your wiki can be edited by third parties. + +## insufficient checking for symlinks in srcdir path + +Ikiwiki did not check if path to the srcdir to contained a symlink. If an +attacker had commit access to the directories in the path, they could +change it to a symlink, causing ikiwiki to read and publish files that were +not intended to be published. (But not write to them due to other checks.) + +In most configurations, this is not exploitable, because the srcdir is +checked out of revision control, but the directories leading up to it are +not. Or, the srcdir is a single subdirectory of a project in revision +control (ie, `ikiwiki/doc`), and if the subdirectory were a symlink, +ikiwiki would still typically not follow it. + +There are at least two configurations where this is exploitable: + +* If the srcdir is a deeper subdirectory of a project. For example if it is + `project/foo/doc`, an an attacker can replace `foo` with a symlink to a + directory containing a `doc` directory (not a symlink), then ikiwiki + would follow the symlink. +* If the path to the srcdir in ikiwiki's configuration ended in "/", + and the srcdir is a single subdirectory of a project, (ie, + `ikiwiki/doc/`), the srcdir could be a symlink and ikiwiki would not + notice. + +This security hole was discovered on 26 November 2007 and fixed the same +da with the release of ikiwiki 2.14. I recommend upgrading to this version +if your wiki can be committed to by third parties. Alternatively, don't use +a trailing slash in the srcdir, and avoid the (unusual) configurations that +allow the security hole to be exploited. |