nfsd in the Linux kernel before 2.6.28.9 does not drop the CAP_MKNOD capability before handling a user request in a thread, which allows local users to create device nodes, as demonstrated on a filesystem that has been exported with the root_squash option.

cronic before 3 allows local users to write to arbitrary files via a symlink attack on a (1) cronic.out.$$, (2) cronic.err.$$, or (3) cronic.trace.$$ file in /tmp.

snapd 2.54.2 did not properly validate the location of the snap-confine binary. A local attacker who can hardlink this binary to another location to cause snap-confine to execute other arbitrary binaries and hence gain privilege escalation. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1

htpasswd and htdigest in Apache 2.0a9, 1.3.14, and others allows local users to overwrite arbitrary files via a symlink attack.

Perl module Data::UUID from CPAN version 1.219 vulnerable to symlink attacks

Tar.php in Archive_Tar through 1.4.11 allows write operations with Directory Traversal due to inadequate checking of symbolic links, a related issue to CVE-2020-28948.

Samba before versions 4.6.1, 4.5.7 and 4.4.11 are vulnerable to a malicious client using a symlink race to allow access to areas of the server file system not exported under the share definition.

In libXfont before 1.5.4 and libXfont2 before 2.0.3, a local attacker can open (but not read) files on the system as root, triggering tape rewinds, watchdogs, or similar mechanisms that can be triggered by opening files.

squashfs_opendir in unsquash-2.c in Squashfs-Tools 4.5 allows Directory Traversal, a different vulnerability than CVE-2021-40153. A squashfs filesystem that has been crafted to include a symbolic link and then contents under the same filename in a filesystem can cause unsquashfs to first create the symbolic link pointing outside the expected directory, and then the subsequent write operation will cause the unsquashfs process to write through the symbolic link elsewhere in the filesystem.

NLnet Labs Unbound, up to and including version 1.12.0, and NLnet Labs NSD, up to and including version 4.3.3, contain a local vulnerability that would allow for a local symlink attack. When writing the PID file, Unbound and NSD create the file if it is not there, or open an existing file for writing. In case the file was already present, they would follow symlinks if the file happened to be a symlink instead of a regular file. An additional chown of the file would then take place after it was written, making the user Unbound/NSD is supposed to run as the new owner of the file. If an attacker has local access to the user Unbound/NSD runs as, she could create a symlink in place of the PID file pointing to a file that she would like to erase. If then Unbound/NSD is killed and the PID file is not cleared, upon restarting with root privileges, Unbound/NSD will rewrite any file pointed at by the symlink. This is a local vulnerability that could create a Denial of Service of the system Unbound/NSD is running on. It requires an attacker having access to the limited permission user Unbound/NSD runs as and point through the symlink to a critical file on the system.

The init script in the Debian x11-common package before 1:7.6+12 is vulnerable to a symlink attack that can lead to a privilege escalation during package installation.

In KDE Ark before 20.08.1, a crafted TAR archive with symlinks can install files outside the extraction directory, as demonstrated by a write operation to a user's home directory.

foomatic-rip filter v4.0.12 and prior used insecurely creates temporary files for storage of PostScript data by rendering the data when the debug mode was enabled. This flaw may be exploited by a local attacker to conduct symlink attacks by overwriting arbitrary files accessible with the privileges of the user running the foomatic-rip universal print filter.

Hardlink before 0.1.2 operates on full file system objects path names which can allow a local attacker to use this flaw to conduct symlink attacks.

atop: symlink attack possible due to insecure tempfile handling

foomatic-rip filter, all versions, used insecurely creates temporary files for storage of PostScript data by rendering the data when the debug mode was enabled. This flaw may be exploited by a local attacker to conduct symlink attacks by overwriting arbitrary files accessible with the privileges of the user running the foomatic-rip universal print filter.

guilt 0.27 allows local users to overwrite arbitrary files via a symlink attack on a guilt.log.[PID] temporary file.

ikiwiki before 3.20110608 allows remote attackers to hijack root's tty and run symlink attacks.

Inappropriate implementation in Google Updater in Google Chrome on Windows prior to 94.0.4606.54 allowed a remote attacker to perform local privilege escalation via a crafted file.

In tesseract 2.03 and 2.04, an attacker can rewrite an arbitrary user file by guessing the PID and creating a link to the user's file.

linki.py in ekg 2005-06-05 and earlier allows local users to overwrite or create arbitrary files via a symlink attack on temporary files.

The npm package "tar" (aka node-tar) before versions 4.4.16, 5.0.8, and 6.1.7 has an arbitrary file creation/overwrite and arbitrary code execution vulnerability. node-tar aims to guarantee that any file whose location would be modified by a symbolic link is not extracted. This is, in part, achieved by ensuring that extracted directories are not symlinks. Additionally, in order to prevent unnecessary stat calls to determine whether a given path is a directory, paths are cached when directories are created. This logic was insufficient when extracting tar files that contained both a directory and a symlink with the same name as the directory, where the symlink and directory names in the archive entry used backslashes as a path separator on posix systems. The cache checking logic used both `\` and `/` characters as path separators, however `\` is a valid filename character on posix systems. By first creating a directory, and then replacing that directory with a symlink, it was thus possible to bypass node-tar symlink checks on directories, essentially allowing an untrusted tar file to symlink into an arbitrary location and subsequently extracting arbitrary files into that location, thus allowing arbitrary file creation and overwrite. Additionally, a similar confusion could arise on case-insensitive filesystems. If a tar archive contained a directory at `FOO`, followed by a symbolic link named `foo`, then on case-insensitive file systems, the creation of the symbolic link would remove the directory from the filesystem, but _not_ from the internal directory cache, as it would not be treated as a cache hit. A subsequent file entry within the `FOO` directory would then be placed in the target of the symbolic link, thinking that the directory had already been created. These issues were addressed in releases 4.4.16, 5.0.8 and 6.1.7. The v3 branch of node-tar has been deprecated and did not receive patches for these issues. If you are still using a v3 release we recommend you update to a more recent version of node-tar. If this is not possible, a workaround is available in the referenced GHSA-9r2w-394v-53qc.

The npm package "tar" (aka node-tar) before versions 4.4.18, 5.0.10, and 6.1.9 has an arbitrary file creation/overwrite and arbitrary code execution vulnerability. node-tar aims to guarantee that any file whose location would be modified by a symbolic link is not extracted. This is, in part, achieved by ensuring that extracted directories are not symlinks. Additionally, in order to prevent unnecessary stat calls to determine whether a given path is a directory, paths are cached when directories are created. This logic was insufficient when extracting tar files that contained both a directory and a symlink with names containing unicode values that normalized to the same value. Additionally, on Windows systems, long path portions would resolve to the same file system entities as their 8.3 "short path" counterparts. A specially crafted tar archive could thus include a directory with one form of the path, followed by a symbolic link with a different string that resolves to the same file system entity, followed by a file using the first form. By first creating a directory, and then replacing that directory with a symlink that had a different apparent name that resolved to the same entry in the filesystem, it was thus possible to bypass node-tar symlink checks on directories, essentially allowing an untrusted tar file to symlink into an arbitrary location and subsequently extracting arbitrary files into that location, thus allowing arbitrary file creation and overwrite. These issues were addressed in releases 4.4.18, 5.0.10 and 6.1.9. The v3 branch of node-tar has been deprecated and did not receive patches for these issues. If you are still using a v3 release we recommend you update to a more recent version of node-tar. If this is not possible, a workaround is available in the referenced GHSA-qq89-hq3f-393p.

pithos before 0.3.5 allows overwrite of arbitrary files via symlinks.

ocrodjvu 0.4.6-1 on Debian GNU/Linux allows local users to modify arbitrary files via a symlink attack on temporary files that are generated when Cuneiform is invoked as the OCR engine.

Race condition in cpio 2.6 and earlier allows local users to modify permissions of arbitrary files via a hard link attack on a file while it is being decompressed, whose permissions are changed by cpio after the decompression is complete.

The mysqlaccess script in MySQL 4.0.23 and earlier, 4.1.x before 4.1.10, 5.0.x before 5.0.3, and other versions including 3.x, allows local users to overwrite arbitrary files or read temporary files via a symlink attack on temporary files.

KDE before 3.3.0 does not properly handle when certain symbolic links point to "stale" locations, which could allow local users to create or truncate arbitrary files.

The postfix.postinst script in the Debian GNU/Linux and Ubuntu postfix 2.5.5 package grants the postfix user write access to /var/spool/postfix/pid, which might allow local users to conduct symlink attacks that overwrite arbitrary files.

Xfig, possibly 3.2.5, allows local users to read and write arbitrary files via a symlink attack on the (1) xfig-eps[PID], (2) xfig-pic[PID].pix, (3) xfig-pic[PID].err, (4) xfig-pcx[PID].pix, (5) xfig-xfigrc[PID], (6) xfig[PID], (7) xfig-print[PID], (8) xfig-export[PID].err, (9) xfig-batch[PID], (10) xfig-exp[PID], or (11) xfig-spell.[PID] temporary files, where [PID] is a process ID.

fr-archive-libarchive.c in GNOME file-roller through 3.36.1 allows Directory Traversal during extraction because it lacks a check of whether a file's parent is a symlink to a directory outside of the intended extraction location.

i2myspell in myspell 3.1 allows local users to overwrite arbitrary files via a symlink attack on (1) /tmp/i2my#####.1 and (2) /tmp/i2my#####.2 temporary files.

Mercurial prior to version 4.3 is vulnerable to a missing symlink check that can malicious repositories to modify files outside the repository

Qemu before version 2.9 is vulnerable to an improper link following when built with the VirtFS. A privileged user inside guest could use this flaw to access host file system beyond the shared folder and potentially escalating their privileges on a host.

The postinst script in the tomcat6 package before 6.0.45+dfsg-1~deb7u4 on Debian wheezy, before 6.0.35-1ubuntu3.9 on Ubuntu 12.04 LTS and on Ubuntu 14.04 LTS; the tomcat7 package before 7.0.28-4+deb7u8 on Debian wheezy, before 7.0.56-3+deb8u6 on Debian jessie, before 7.0.52-1ubuntu0.8 on Ubuntu 14.04 LTS, and on Ubuntu 12.04 LTS, 16.04 LTS, and 16.10; and the tomcat8 package before 8.0.14-1+deb8u5 on Debian jessie, before 8.0.32-1ubuntu1.3 on Ubuntu 16.04 LTS, before 8.0.37-1ubuntu0.1 on Ubuntu 16.10, and before 8.0.38-2ubuntu1 on Ubuntu 17.04 might allow local users with access to the tomcat account to obtain sensitive information or gain root privileges via a symlink attack on the Catalina localhost directory.

ltpmenu in ltp 20060918 allows local users to overwrite arbitrary files via a symlink attack on a /tmp/runltp.mainmenu.##### temporary file.

Mumble before 1.3.4 allows remote code execution if a victim navigates to a crafted URL on a server list and clicks on the Open Webpage text.

axiom-test.sh in axiom 20100701-1.1 uses tempfile to create a safe temporary file but appends a suffix to the original filename and writes to this new filename, which allows local users to overwrite arbitrary files via a symlink attack on the new filename.

syncevo/installcheck-local.sh in syncevolution before 1.3.99.7 uses mktemp to create a safe temporary file but appends a suffix to the original filename and writes to this new filename, which allows local users to overwrite arbitrary files via a symlink attack on the new filename.

The to-upgrade plugin in feta 1.4.16 allows local users to overwrite arbitrary files via a symlink on the (1) /tmp/feta.install.$USER and (2) /tmp/feta.avail.$USER temporary files.

The pg_ctlcluster script in postgresql-common package in Debian wheezy before 134wheezy5, in Debian jessie before 165+deb8u2, in Debian unstable before 178, in Ubuntu 12.04 LTS before 129ubuntu1.2, in Ubuntu 14.04 LTS before 154ubuntu1.1, in Ubuntu 16.04 LTS before 173ubuntu0.1, in Ubuntu 17.04 before 179ubuntu0.1, and in Ubuntu 17.10 before 184ubuntu1.1 allows local users to gain root privileges via a symlink attack on a logfile in /var/log/postgresql.

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.8 and earlier, when starting the cupsd server with a Listen configuration item pointing to a symbolic link, the cupsd process can be caused to perform an arbitrary chmod of the provided argument, providing world-writable access to the target. Given that cupsd is often running as root, this can result in the change of permission of any user or system files to be world writable. Given the aforementioned Ubuntu AppArmor context, on such systems this vulnerability is limited to those files modifiable by the cupsd process. In that specific case it was found to be possible to turn the configuration of the Listen argument into full control over the cupsd.conf and cups-files.conf configuration files. By later setting the User and Group arguments in cups-files.conf, and printing with a printer configured by PPD with a `FoomaticRIPCommandLine` argument, arbitrary user and group (not root) command execution could be achieved, which can further be used on Ubuntu systems to achieve full root command execution. Commit ff1f8a623e090dee8a8aadf12a6a4b25efac143d contains a patch for the issue.

mkmailpost in newsgate 1.6 allows local users to overwrite arbitrary files via a symlink attack on a /tmp/mmp##### temporary file.

A flaw was found in Mercurial before 4.9. It was possible to use symlinks and subrepositories to defeat Mercurial's path-checking logic and write files outside a repository.

gccross in dpkg-cross 2.3.0 allows local users to overwrite arbitrary files via a symlink attack on the tmp/gccross2.log temporary file. NOTE: the vendor disputes this vulnerability, stating that "There is no sense in this bug - the script ... is called under specific cross-building environments within a chroot.

os-prober in os-prober 1.17 allows local users to overwrite arbitrary files via a symlink attack on the (1) /tmp/mounted-map or (2) /tmp/raided-map temporary file. NOTE: the vendor disputes this issue, stating "the insecure code path should only ever run inside a d-i environment, which has no non-root users.