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CVE request: automake: insecure use of /tmp in install-sh
From: Vasyl Kaigorodov <vkaigoro () redhat com>
Date: Fri, 12 Sep 2014 14:29:40 +0200
Hello, It was discovered [1] that there's an issue in how automake handles temp directories. When the destination directory does not exist, install-sh checks if "mkdir -p" works, but it does so in an insecure way. Here are the relevant parts of the code: mkdirprog=${MKDIRPROG-mkdir} # ... tmpdir=${TMPDIR-/tmp}/ins$RANDOM-$$ trap 'ret=$?; rmdir "$tmpdir/d" "$tmpdir" 2>/dev/null; exit $ret' 0 if (umask $mkdir_umask && exec $mkdirprog $mkdir_mode -p -- "$tmpdir/d") >/dev/null 2>&1 then # ... rmdir "$tmpdir/d" "$tmpdir" else # ... In some shells (such as dash) $RANDOM is not set, so $tmpdir is easily predictable. Moreover, "mkdir -p" follows symlinks to existing directories. Local attacker can exploit this to create or remove empty directories named "d". (But on modern Linux systems this is mitigated by the protected_symlinks feature.) References: [1]: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=760455 [2]: https://bugzilla.redhat.com/show_bug.cgi?id=1140725 [3]: https://bugs.gentoo.org/show_bug.cgi?id=522638 Can a CVE ID be assigned to this please? Thanks. -- Vasyl Kaigorodov | Red Hat Product Security PGP: 0xABB6E828 A7E0 87FF 5AB5 48EB 47D0 2868 217B F9FC ABB6 E828
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- CVE request: automake: insecure use of /tmp in install-sh Vasyl Kaigorodov (Sep 12)