An issue was discovered in Singularity 3.1.0 to 3.2.0-rc2, a malicious user with local/network access to the host system (e.g. ssh) could exploit this vulnerability due to insecure permissions allowing a user to edit files within `/run/singularity/instances/sing/<user>/<instance>`. The manipulation of those files can change the behavior of the starter-suid program when instances are joined resulting in potential privilege escalation on the host.

This update for singularity fixes the following issues :

  - New version 3.6.0. This version introduces a new     signature format for SIF images, and changes to the     signing / verification code to address the following     security problems :

  - CVE-2020-13845, boo#1174150 In Singularity 3.x versions     below 3.6.0, issues allow the ECL to be bypassed by a     malicious user.

  - CVE-2020-13846, boo#1174148 In Singularity 3.5 the --all     / -a option to singularity verify returns success even     when some objects in a SIF container are not signed, or     cannot be verified.

  - CVE-2020-13847, boo#1174152 In Singularity 3.x versions     below 3.6.0, Singularity's sign and verify commands do     not sign metadata found in the global header or data     object descriptors of a SIF file, allowing an attacker     to cause unexpected behavior. A signed container may     verify successfully, even when it has been modified in     ways that could be exploited to cause malicious     behavior.

  - New features / functionalities

  - A new '--legacy-insecure' flag to verify allows     verification of SIF signatures in the old, insecure     format.

  - A new '-l / --logs' flag for instance list that shows     the paths to instance STDERR / STDOUT log files.

  - The --json output of instance list now include paths to     STDERR / STDOUT log files.

  - Singularity now supports the execution of minimal     Docker/OCI containers that do not contain /bin/sh, e.g.
    docker://hello-world.

  - A new cache structure is used that is concurrency safe     on a filesystem that supports atomic rename. If you     downgrade to Singularity 3.5 or older after using 3.6     you will need to run singularity cache clean.

  - A plugin system rework adds new hook points that will     allow the development of plugins that modify behavior of     the runtime. An image driver concept is introduced for     plugins to support new ways of handling image and     overlay mounts. Plugins built for <=3.5 are not     compatible with 3.6.

  - The --bind flag can now bind directories from a SIF or     ext3 image into a container.

  - The --fusemount feature to mount filesystems to a     container via FUSE drivers is now a supported feature     (previously an experimental hidden flag).

  - This permits users to mount e.g. sshfs and cvmfs     filesystems to the container at runtime.

  - A new -c/--config flag allows an alternative     singularity.conf to be specified by the root user, or     all users in an unprivileged installation.

  - A new --env flag allows container environment variables     to be set via the Singularity command line.

  - A new --env-file flag allows container environment     variables to be set from a specified file.

  - A new --days flag for cache clean allows removal of     items older than a specified number of days. Replaces     the --name flag which is not generally useful as the     cache entries are stored by hash, not a friendly name.

  - Changed defaults / behaviours

  - New signature format (see security fixes above).

  - Fixed spacing of singularity instance list to be     dynamically changing based off of input lengths instead     of fixed number of spaces to account for long instance     names.

  - Environment variables prefixed with SINGULARITYENV_     always take precedence over variables without     SINGULARITYENV_ prefix.

  - The %post build section inherits environment variables     from the base image.

  - %files from ... will now follow symlinks for sources     that are directly specified, or directly resolved from a     glob pattern. It will not follow symlinks found through     directory traversal. This mirrors Docker multi-stage     COPY behaviour.

  - Restored the CWD mount behaviour of v2, implying that     CWD path is not recreated inside container and any     symlinks in the CWD path are not resolved anymore to     determine the destination path inside container.

  - The %test build section is executed the same manner as     singularity test image.

    --fusemount with the container: default directive will     foreground the FUSE process. Use container-daemon: for     previous behavior.

  - Deprecate -a / --all option to sign/verify as new     signature behavior makes this the default.

  - For more information about upstream changes, please     check:
    https://github.com/hpcng/singularity/blob/master/CHANGEL     OG.md

  - Removed --name flag for cache clean; replaced with
    --days.

Security fix for CVE-2019-11328

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

ID	Name	Product	Family	Severity
138979	openSUSE Security Update : singularity (openSUSE-2020-1037)	Nessus	SuSE Local Security Checks	high
125423	Fedora 29 : singularity (2019-25ecc42592)	Nessus	Fedora Local Security Checks	high
125378	Fedora 30 : singularity (2019-da2ed3b0b5)	Nessus	Fedora Local Security Checks	high
125376	Fedora 28 : singularity (2019-9f48c6fedc)	Nessus	Fedora Local Security Checks	high

Detections

Analytics

CVE-2019-11328

high

Tenable Plugins

high

high

high

high