FreshPorts - VuXML

Todd C. Miller reports:

When sudo is configured to allow a user to run commands as an arbitrary user via the ALL keyword in a Runas specification, it is possible to run commands as root by specifying the user ID -1 or 4294967295.

This can be used by a user with sufficient sudo privileges to run commands as root even if the Runas specification explicitly disallows root access as long as the ALL keyword is listed first in the Runas specification.

Log entries for commands run this way will list the target user as 4294967295 instead of root. In addition, PAM session modules will not be run for the command.

< 1.8.28

Todd Miller reports:

Sudo supports granting access to commands on a per-host basis. The host specification may be in the form of a host name, a netgroup, an IP address, or an IP network (an IP address with an associated netmask).

When IPv6 support was added to sudo, a bug was introduced that caused the IPv6 network matching code to be called when an IPv4 network address does not match. Depending on the value of the uninitialized portion of the IPv6 address, it is possible for the IPv4 network number to match when it should not. This bug only affects IP network matching and does not affect simple IP address matching.

The reported configuration that exhibited the bug was an LDAP-based sudo installation where the sudoRole object contained multiple sudoHost entries, each containing a different IPv4 network. File-based sudoers should be affected as well as the same matching code is used.

le 1.8.4_1

MITRE reports:

sudoedit in Sudo before 1.8.15 allows local users to gain privileges via a symlink attack on a file whose full path is defined using multiple wildcards in /etc/sudoers, as demonstrated by "/home/*/*/file.txt."

< 1.8.15

Todd Miller reports:

Beginning with sudo version 1.7.0 it has been possible to grant permission to run a command using a specified group via sudo's -g option (run as group), if allowed by the sudoers file. A flaw exists in sudo's password checking logic that allows a user to run a command with only the group changed without being prompted for a password.

ge 1.7.0 lt 1.7.4.5

Todd C. Miller reports:

A potential information leak in sudoedit that could be used to test for the existence of directories not normally accessible to the user in certain circumstances. When creating a new file, sudoedit checks to make sure the parent directory of the new file exists before running the editor. However, a race condition exists if the invoking user can replace (or create) the parent directory. If a symbolic link is created in place of the parent directory, sudoedit will run the editor as long as the target of the link exists.If the target of the link does not exist, an error message will be displayed. The race condition can be used to test for the existence of an arbitrary directory. However, it _cannot_ be used to write to an arbitrary location.

< 1.9.5

Todd Miller reports:

The flaw may allow someone with physical access to a machine that is not password-protected to run sudo commands without knowing the logged in user's password. On systems where sudo is the principal way of running commands as root, such as on Ubuntu and Mac OS X, there is a greater chance that the logged in user has run sudo before and thus that an attack would succeed.

< 1.8.6.p7

Todd C. Miller reports:

Sudo's pwfeedback option can be used to provide visual feedback when the user is inputting their password. For each key press, an asterisk is printed. This option was added in response to user confusion over how the standard Password: prompt disables the echoing of key presses. While pwfeedback is not enabled by default in the upstream version of sudo, some systems, such as Linux Mint and Elementary OS, do enable it in their default sudoers files.

Due to a bug, when the pwfeedback option is enabled in the sudoers file, a user may be able to trigger a stack-based buffer overflow. This bug can be triggered even by users not listed in the sudoers file. There is no impact unless pwfeedback has been enabled.

< 1.8.31

Todd C. Miller reports:

When invoked as sudoedit, the same set of command line options are now accepted as for sudo -e. The -H and -P options are now rejected for sudoedit and sudo -e which matches the sudo 1.7 behavior. This is part of the fix for CVE-2021-3156.

Fixed a potential buffer overflow when unescaping backslashes in the command's arguments. Normally, sudo escapes special characters when running a command via a shell (sudo -s or sudo -i). However, it was also possible to run sudoedit with the -s or -i flags in which case no escaping had actually been done, making a buffer overflow possible. This fixes CVE-2021-3156.

< 1.9.5p2

Todd C. Miller reports:

A flaw exists in sudo's noexec functionality that may allow a user with sudo privileges to run additional commands even when the NOEXEC tag has been applied to a command that uses the wordexp() function.

ge 1.6.8 lt 1.8.18p1

Todd Miller reports:

A (potentially malicious) program run by a user with sudo access may be able to bypass the "tty_ticket" constraints. In order for this to succeed there must exist on the machine a terminal device that the user has previously authenticated themselves on via sudo within the last time stamp timeout (5 minutes by default).

< 1.8.6.p7