shadow vulnerabilities

CVE-2024-56433

shadow-utils (aka shadow) 4.4 through 4.17.0 establishes a default /etc/subuid behavior (e.g., uid 100000 through 165535 for the first user account) that can realistically conflict with the uids of users defined on locally administered networks, potentially leading to account takeover, e.g., by leveraging newuidmap for access to an NFS home directory (or same-host resources in the case of remote logins by these local network users). NOTE: it may also be argued that system administrators should not have assigned uids, within local networks, that are within the range that can occur in /etc/subuid.

Shadow-utils: possible password leak during passwd(1) change

A flaw was found in shadow-utils. When asking for a new password, shadow-utils asks the password twice. If the password fails on the second attempt, shadow-utils fails in cleaning the buffer used to store the first entry. This may allow an attacker with enough access to retrieve the password from the memory.

• Update to 1:4.13+dfsg1-1+deb12u1

CVE-2023-29383

In Shadow 4.13, it is possible to inject control characters into fields provided to the SUID program chfn (change finger). Although it is not possible to exploit this directly (e.g., adding a new user fails because \n is in the block list), it is possible to misrepresent the /etc/passwd file when viewed. Use of \r manipulations and Unicode characters to work around blocking of the : character make it possible to give the impression that a new user has been added. In other words, an adversary may be able to convince a system administrator to take the system offline (an indirect, social-engineered denial of service) by demonstrating that "cat /

• Update to 1:4.13+dfsg1-1+deb12u1

CVE-2017-20002

The Debian shadow package before 1:4.5-1 for Shadow incorrectly lists pts/0 and pts/1 as physical terminals in /etc/securetty. This allows local users to login as password-less users even if they are connected by non-physical means such as SSH (hence bypassing PAM's nullok_secure configuration). This notably affects environments such as virtual machines automatically generated with a default blank root password, allowing all local users to escalate privileges.

• Update to 1:4.5-1

CVE-2019-19882

shadow 4.8, in certain circumstances affecting at least Gentoo, Arch Linux, and Void Linux, allows local users to obtain root access because setuid programs are misconfigured. Specifically, this affects shadow 4.8 when compiled using --with-libpam but without explicitly passing --disable-account-tools-setuid, and without a PAM configuration suitable for use with setuid account management tools. This combination leads to account management tools (groupadd, groupdel, groupmod, useradd, userdel, usermod) that can easily be used by unprivileged local users to escalate privileges to root in multiple ways. This issue became much more relevant in ap

• Update to 1:4.8.1-1

CVE-2013-4235

shadow: TOCTOU (time-of-check time-of-use) race condition when copying and removing directory trees

• Update to 1:4.12.3+dfsg1-1

CVE-2005-4890

There is a possible tty hijacking in shadow 4.x before 4.1.5 and sudo 1.x before 1.7.4 via "su - user -c program". The user session can be escaped to the parent session by using the TIOCSTI ioctl to push characters into the input buffer to be read by the next process.

• Update to 1:4.1.5-1

CVE-2017-2616

A race condition was found in util-linux before 2.32.1 in the way su handled the management of child processes. A local authenticated attacker could use this flaw to kill other processes with root privileges under specific conditions.

• Update to 1:4.4-4

CVE-2018-7169

An issue was discovered in shadow 4.5. newgidmap (in shadow-utils) is setuid and allows an unprivileged user to be placed in a user namespace where setgroups(2) is permitted. This allows an attacker to remove themselves from a supplementary group, which may allow access to certain filesystem paths if the administrator has used "group blacklisting" (e.g., chmod g-rwx) to restrict access to paths. This flaw effectively reverts a security feature in the kernel (in particular, the /proc/self/setgroups knob) to prevent this sort of privilege escalation.

• Update to 1:4.7-1

CVE-2017-12424

In shadow before 4.5, the newusers tool could be made to manipulate internal data structures in ways unintended by the authors. Malformed input may lead to crashes (with a buffer overflow or other memory corruption) or other unspecified behaviors. This crosses a privilege boundary in, for example, certain web-hosting environments in which a Control Panel allows an unprivileged user account to create subaccounts.

• Update to 1:4.5-1

CVE-2016-6252

Integer overflow in shadow 4.2.1 allows local users to gain privileges via crafted input to newuidmap.

• Update to 1:4.4-1

CVE-2011-0721

Multiple CRLF injection vulnerabilities in (1) chfn and (2) chsh in shadow 1:4.1.4 allow local users to add new users or groups to /etc/passwd via the GECOS field.

• Update to 1:4.1.4.2+svn3283-3

CVE-2008-5394

/bin/login in shadow 4.0.18.1 in Debian GNU/Linux, and probably other Linux distributions, allows local users in the utmp group to overwrite arbitrary files via a symlink attack on a temporary file referenced in a line (aka ut_line) field in a utmp entry.

• Update to 1:4.1.1-6

CVE-2007-5686

initscripts in rPath Linux 1 sets insecure permissions for the /var/log/btmp file, which allows local users to obtain sensitive information regarding authentication attempts. NOTE: because sshd detects the insecure permissions and does not log certain events, this also prevents sshd from logging failed authentication attempts by remote attackers.

CVE-2006-3378

passwd command in shadow in Ubuntu 5.04 through 6.06 LTS, when called with the -f, -g, or -s flag, does not check the return code of a setuid call, which might allow local users to gain root privileges if setuid fails in cases such as PAM failures or resource limits.

• Update to 1:4.0.14-1

CVE-2006-1174

useradd in shadow-utils before 4.0.3, and possibly other versions before 4.0.8, does not provide a required argument to the open function when creating a new user mailbox, which causes the mailbox to be created with unpredictable permissions and possibly allows attackers to read or modify the mailbox.

• Update to 1:4.0.15-10

CVE-2006-1844

The Debian installer for the (1) shadow 4.0.14 and (2) base-config 2.53.10 packages includes sensitive information in world-readable log files, including preseeded passwords and pppoeconf passwords, which might allow local users to gain privileges.

• Update to 1:4.0.14-9

CVE-2006-1376

The installation of Debian GNU/Linux 3.1r1 from the network install CD creates /var/log/debian-installer/cdebconf with world writable permissions, which allows local users to cause a denial of service (disk consumption).

• Update to 1:4.0.14-9

CVE-2004-1001

Unknown vulnerability in the passwd_check function in Shadow 4.0.4.1, and possibly other versions before 4.0.5, allows local users to conduct unauthorized activities when an error from a pam_chauthtok function call is not properly handled.

• Update to 1:4.0.3-35