diff options
| -rw-r--r-- | .hgsigs | 1 | ||||
| -rw-r--r-- | .hgtags | 1 | ||||
| -rw-r--r-- | CHANGES | 25 | ||||
| -rw-r--r-- | buffer.c | 1 | ||||
| -rw-r--r-- | debian/changelog | 6 | ||||
| -rw-r--r-- | svr-authpubkey.c | 17 | ||||
| -rw-r--r-- | svr-authpubkeyoptions.c | 7 | ||||
| -rw-r--r-- | svr-tcpfwd.c | 2 | ||||
| -rw-r--r-- | sysoptions.h | 2 |
9 files changed, 57 insertions, 5 deletions
@@ -22,3 +22,4 @@ af074dbcb68ff8670b3818e0d66d5dc6f1bd5877 0 iQIcBAABCgAGBQJWVdQfAAoJEPSYMBLCC7qs+ fd1981f41c626a969f07b4823848deaefef3c8aa 0 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 70705edee9dd29cd3d410f19fbd15cc3489313e2 0 iQIcBAABCgAGBQJW7CQRAAoJEESTFJTynGdzTj0QAJL38CKSZthBAeI9c6B+IlwIeT6kPZaPqk1pkycCTWOe87NiNU9abrsF+JrjTuRQiO1EpM2IvfQEIXTijUcMxvld3PnzrZDDv6UvBLtOkn3i++HSVRO0MOuTKI8gFDEPUxRtcaCKXEbqYnf1OTK25FT09Vb//qP9mK1thvlLJmbV+D2a9MkMK66rom1d1h+347IsuwsM+ycHjB80VVAQLA7VYLC5YIwmL17dSmcQLvetfikAMwwmUE+KES4qiLSaqOcAWcKcU67RZzgMMv5o0rESlQmv1nj0mHZtHoUR71sd21emPaRXLOr0oT5YogWUphKq2qVthRn2B06+vd3hPdtn92CmJw9j7zT2jl4OeSjNm9qfAajsRzHIANssFxkGAb7w/LxcMoO29JC+01iUUJMdOVm+4Ns6wGI7qxssWPKdB+VbQUDlHrXLR+sopO524uhkYoWB6DVfTj4R6tImaHtj5/VXON0lsYaLGj8cSH60emL6nNQ0lYV/bSlk6l0s+0x3uXGZnp9oKA+vqMzHfG3vJeMm6KUqtFVjUsYx+q8nHm5/SlWxj1EwnkH8s8ELKZAUXjd76nWEwJ7JFRNRSQWvjOUh3/rsOo4JopzZXPsjCjm+Vql9TG0X6hB21noai32oD5RvfhtR/NX6sXNS5TKZz/j/cMsMnAAsSKb6W7Jm 9030ffdbe5625e35ed7189ab84a41dfc8d413e9c 0 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 +5c9207ceedaea794f958224c19214d66af6e2d56 0 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 @@ -54,3 +54,4 @@ cbd674d63cd4f3781464a8d4056a5506c8ae926f DROPBEAR_2015.67 78b12b6549be08b0bea3da329b2578060a76ca31 DROPBEAR_2016.72 309e1c4a87682b6ca7d80b8555a1db416c3cb7ac DROPBEAR_2016.73 0ed3d2bbf956cb8a9bf0f4b5a86b7dd9688205cb DROPBEAR_2016.74 +c31276613181c5cff7854e7ef586ace03424e55e DROPBEAR_2017.75 @@ -1,3 +1,28 @@ +2017.75 - 18 May 2017 + +- Security: Fix double-free in server TCP listener cleanup + A double-free in the server could be triggered by an authenticated user if + dropbear is running with -a (Allow connections to forwarded ports from any host) + This could potentially allow arbitrary code execution as root by an authenticated user. + Affects versions 2013.56 to 2016.74. Thanks to Mark Shepard for reporting the crash. + +- Security: Fix information disclosure with ~/.ssh/authorized_keys symlink. + Dropbear parsed authorized_keys as root, even if it were a symlink. The fix + is to switch to user permissions when opening authorized_keys + + A user could symlink their ~/.ssh/authorized_keys to a root-owned file they + couldn't normally read. If they managed to get that file to contain valid + authorized_keys with command= options it might be possible to read other + contents of that file. + This information disclosure is to an already authenticated user. + Thanks to Jann Horn of Google Project Zero for reporting this. + +- Generate hostkeys with dropbearkey atomically and flush to disk with fsync + Thanks to Andrei Gherzan for a patch + +- Fix out of tree builds with bundled libtom + Thanks to Henrik Nordström and Peter Krefting for patches. + 2016.74 - 21 July 2016 - Security: Message printout was vulnerable to format string injection. @@ -109,6 +109,7 @@ void buf_setlen(buffer* buf, unsigned int len) { dropbear_exit("Bad buf_setlen"); } buf->len = len; + buf->pos = MIN(buf->pos, buf->len); } /* Increment the length of the buffer */ diff --git a/debian/changelog b/debian/changelog index 87edb50..037805f 100644 --- a/debian/changelog +++ b/debian/changelog @@ -1,3 +1,9 @@ +dropbear (2017.75-0.1) unstable; urgency=low + + * New upstream release. + + -- Matt Johnston <matt@ucc.asn.au> Thu, 18 May 2017 22:51:57 +0800 + dropbear (2016.74-0.1) unstable; urgency=low * New upstream release. diff --git a/svr-authpubkey.c b/svr-authpubkey.c index 90d0d2c..acc660d 100644 --- a/svr-authpubkey.c +++ b/svr-authpubkey.c @@ -201,6 +201,8 @@ static int checkpubkey(char* algo, unsigned int algolen, unsigned int len, pos; buffer * options_buf = NULL; int line_num; + uid_t origuid; + gid_t origgid; TRACE(("enter checkpubkey")) @@ -227,8 +229,21 @@ static int checkpubkey(char* algo, unsigned int algolen, snprintf(filename, len + 22, "%s/.ssh/authorized_keys", ses.authstate.pw_dir); - /* open the file */ + /* open the file as the authenticating user. */ + origuid = getuid(); + origgid = getgid(); + if ((setegid(ses.authstate.pw_gid)) < 0 || + (seteuid(ses.authstate.pw_uid)) < 0) { + dropbear_exit("Failed to set euid"); + } + authfile = fopen(filename, "r"); + + if ((seteuid(origuid)) < 0 || + (setegid(origgid)) < 0) { + dropbear_exit("Failed to revert euid"); + } + if (authfile == NULL) { goto out; } diff --git a/svr-authpubkeyoptions.c b/svr-authpubkeyoptions.c index a04426e..d08fc2c 100644 --- a/svr-authpubkeyoptions.c +++ b/svr-authpubkeyoptions.c @@ -95,6 +95,7 @@ void svr_pubkey_set_forced_command(struct ChanSess *chansess) { if (chansess->cmd) { /* original_command takes ownership */ chansess->original_command = chansess->cmd; + chansess->cmd = NULL; } else { chansess->original_command = m_strdup(""); } @@ -108,6 +109,9 @@ void svr_pubkey_set_forced_command(struct ChanSess *chansess) { /* Free potential public key options */ void svr_pubkey_options_cleanup() { if (ses.authstate.pubkey_options) { + if (ses.authstate.pubkey_options->forced_command) { + m_free(ses.authstate.pubkey_options->forced_command); + } m_free(ses.authstate.pubkey_options); ses.authstate.pubkey_options = NULL; } @@ -200,8 +204,7 @@ next_option: bad_option: ret = DROPBEAR_FAILURE; - m_free(ses.authstate.pubkey_options); - ses.authstate.pubkey_options = NULL; + svr_pubkey_options_cleanup(); dropbear_log(LOG_WARNING, "Bad public key options at %s:%d", filename, line_num); end: diff --git a/svr-tcpfwd.c b/svr-tcpfwd.c index e5b6d46..207587c 100644 --- a/svr-tcpfwd.c +++ b/svr-tcpfwd.c @@ -199,7 +199,7 @@ static int svr_remotetcpreq() { } else { - tcpinfo->listenaddr = request_addr; + tcpinfo->listenaddr = m_strdup(request_addr); } ret = listen_tcpfwd(tcpinfo); diff --git a/sysoptions.h b/sysoptions.h index 1f357e7..441e3a1 100644 --- a/sysoptions.h +++ b/sysoptions.h @@ -4,7 +4,7 @@ *******************************************************************/ #ifndef DROPBEAR_VERSION -#define DROPBEAR_VERSION "2016.74" +#define DROPBEAR_VERSION "2017.75" #endif #define LOCAL_IDENT "SSH-2.0-dropbear_" DROPBEAR_VERSION |