snapd will follow archived symlinks when unpacking a filesystem
In snapd versions prior to 2.62, snapd failed to properly check the
destination of symbolic links when extracting a snap. The snap format
is a squashfs file-system image and so can contain symbolic links and
other file types. Various file entries within the snap squashfs image
(such as icons and desktop files etc) are directly read by snapd when
it is extracted. An attacker who could convince a user to install a
malicious snap which contained symbolic links at these paths could then
cause snapd to write out the contents of the symbolic link destination
into a world-readable directory. This in-turn could allow an unprivileged
user to gain ac
In snapd versions prior to 2.62, snapd failed to properly check the file
type when extracting a snap. The snap format is a squashfs file-system
image and so can contain files that are non-regular files (such as pipes
or sockets etc). Various file entries within the snap squashfs image
(such as icons etc) are directly read by snapd when it is extracted. An
attacker who could convince a user to install a malicious snap which
contained non-regular files at these paths could then cause snapd to block
indefinitely trying to read from such files and cause a denial of service.
In snapd versions prior to 2.62, when using AppArmor for enforcement of
sandbox permissions, snapd failed to restrict writes to the $HOME/bin
path. In Ubuntu, when this path exists, it is automatically added to
the users PATH. An attacker who could convince a user to install a
malicious snap which used the 'home' plug could use this vulnerability
to install arbitrary scripts into the users PATH which may then be run
by the user outside of the expected snap sandbox and hence allow them
to escape confinement.
The snapctl component within snapd allows a confined snap to interact with the snapd daemon to take certain privileged actions on behalf of the snap. It was found that snapctl did not properly parse command-line arguments, allowing an unprivileged user to trigger an authorised action on behalf of the snap that would normally require administrator privileges to perform. This could possibly allow an unprivileged user to perform a denial of service or similar.
Media · CVSS 5.9EPSS 3,45%Sin corrección publicada
CVE-2019-11840
An issue was discovered in the supplementary Go cryptography library, golang.org/x/crypto, before v0.0.0-20190320223903-b7391e95e576. A flaw was found in the amd64 implementation of the golang.org/x/crypto/salsa20 and golang.org/x/crypto/salsa20/salsa packages. If more than 256 GiB of keystream is generated, or if the counter otherwise grows greater than 32 bits, the amd64 implementation will first generate incorrect output, and then cycle back to previously generated keystream. Repeated keystream bytes can lead to loss of confidentiality in encryption applications, or to predictability in CSPRNG applications.
The Go SSH library (x/crypto/ssh) by default does not verify host keys, facilitating man-in-the-middle attacks. Default behavior changed in commit e4e2799 to require explicitly registering a hostkey verification mechanism.