Canonical Ubuntu Linux 20.04 Lts

Use-after-free vulnerability in the Linux kernel exploitable by a local attacker due to reuse of a DCCP socket with an attached dccps_hc_tx_ccid object as a listener after being released. Fixed in Ubuntu Linux kernel 5.4.0-51.56, 5.3.0-68.63, 4.15.0-121.123, 4.4.0-193.224, 3.13.0.182.191 and 3.2.0-149.196.

GNOME gdk-pixbuf (aka GdkPixbuf) before 2.42.2 allows a denial of service (infinite loop) in lzw.c in the function write_indexes. if c->self_code equals 10, self->code_table[10].extends will assign the value 11 to c. The next execution in the loop will assign self->code_table[11].extends to c, which will give the value of 10. This will make the loop run infinitely. This bug can, for example, be triggered by calling this function with a GIF image with LZW compression that is crafted in a special way.

Aptdaemon performed policykit checks after interacting with potentially untrusted files with elevated privileges. This affected versions prior to 1.1.1+bzr982-0ubuntu34.1, 1.1.1+bzr982-0ubuntu32.3, 1.1.1+bzr982-0ubuntu19.5, 1.1.1+bzr982-0ubuntu14.5.

The aptdaemon DBus interface disclosed file existence disclosure by setting Terminal/DebconfSocket properties, aka GHSL-2020-192 and GHSL-2020-196. This affected versions prior to 1.1.1+bzr982-0ubuntu34.1, 1.1.1+bzr982-0ubuntu32.3, 1.1.1+bzr982-0ubuntu19.5, 1.1.1+bzr982-0ubuntu14.5.

An Ubuntu-specific patch in PulseAudio created a race condition where the snap policy module would fail to identify a client connection from a snap as coming from a snap if SCM_CREDENTIALS were missing, allowing the snap to connect to PulseAudio without proper confinement. This could be exploited by an attacker to expose sensitive information. Fixed in 1:13.99.3-1ubuntu2, 1:13.99.2-1ubuntu2.1, 1:13.99.1-1ubuntu3.8, 1:11.1-1ubuntu7.11, and 1:8.0-0ubuntu3.15.

PackageKit's apt backend mistakenly treated all local debs as trusted. The apt security model is based on repository trust and not on the contents of individual files. On sites with configured PolicyKit rules this may allow users to install malicious packages.

PackageKit provided detailed error messages to unprivileged callers that exposed information about file presence and mimetype of files that the user would be unable to determine on its own.

Ubuntu's packaging of libvirt in 20.04 LTS created a control socket with world read and write permissions. An attacker could use this to overwrite arbitrary files or execute arbitrary code.

In containerd (an industry-standard container runtime) before version 1.2.14 there is a credential leaking vulnerability. If a container image manifest in the OCI Image format or Docker Image V2 Schema 2 format includes a URL for the location of a specific image layer (otherwise known as a “foreign layer†), the default containerd resolver will follow that URL to attempt to download it. In v1.2.x but not 1.3.0 or later, the default containerd resolver will provide its authentication credentials if the server where the URL is located presents an HTTP 401 status code along with registry-specific HTTP headers. If an attacker publishes a public image with a manifest that directs one of the layers to be fetched from a web server they control and they trick a user or system into pulling the image, they can obtain the credentials used for pulling that image. In some cases, this may be the user's username and password for the registry. In other cases, this may be the credentials attached to the cloud virtual instance which can grant access to other cloud resources in the account. The default containerd resolver is used by the cri-containerd plugin (which can be used by Kubernetes), the ctr development tool, and other client programs that have explicitly linked against it. This vulnerability has been fixed in containerd 1.2.14. containerd 1.3 and later are not affected. If you are using containerd 1.3 or later, you are not affected. If you are using cri-containerd in the 1.2 series or prior, you should ensure you only pull images from trusted sources. Other container runtimes built on top of containerd but not using the default resolver (such as Docker) are not affected.

Multiple buffer overflow vulnerabilities were found in the QUIC image decoding process of the SPICE remote display system, before spice-0.14.2-1. Both the SPICE client (spice-gtk) and server are affected by these flaws. These flaws allow a malicious client or server to send specially crafted messages that, when processed by the QUIC image compression algorithm, result in a process crash or potential code execution.

An integer underflow in dpdk versions before 18.11.10 and before 19.11.5 in the `move_desc` function can lead to large amounts of CPU cycles being eaten up in a long running loop. An attacker could cause `move_desc` to get stuck in a 4,294,967,295-count iteration loop. Depending on how `vhost_crypto` is being used this could prevent other VMs or network tasks from being serviced by the busy DPDK lcore for an extended period.

A flaw was found in dpdk in versions before 18.11.10 and before 19.11.5. A complete lack of validation of attacker-controlled parameters can lead to a buffer over read. The results of the over read are then written back to the guest virtual machine memory. This vulnerability can be used by an attacker in a virtual machine to read significant amounts of host memory. The highest threat from this vulnerability is to data confidentiality and system availability.

A flaw was found in dpdk in versions before 18.11.10 and before 19.11.5. A lack of bounds checking when copying iv_data from the VM guest memory into host memory can lead to a large buffer overflow. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A flaw was found in dpdk in versions before 18.11.10 and before 19.11.5. Virtio ring descriptors, and the data they describe are in a region of memory accessible by from both the virtual machine and the host. An attacker in a VM can change the contents of the memory after vhost_crypto has validated it. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A flaw was found in dpdk in versions before 18.11.10 and before 19.11.5. A flawed bounds checking in the copy_data function leads to a buffer overflow allowing an attacker in a virtual machine to write arbitrary data to any address in the vhost_crypto application. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A vulnerability was found in upstream release cryptsetup-2.2.0 where, there's a bug in LUKS2 format validation code, that is effectively invoked on every device/image presenting itself as LUKS2 container. The bug is in segments validation code in file 'lib/luks2/luks2_json_metadata.c' in function hdr_validate_segments(struct crypt_device *cd, json_object *hdr_jobj) where the code does not check for possible overflow on memory allocation used for intervals array (see statement "intervals = malloc(first_backup * sizeof(*intervals));"). Due to the bug, library can be *tricked* to expect such allocation was successful but for far less memory then originally expected. Later it may read data FROM image crafted by an attacker and actually write such data BEYOND allocated memory.

A flaw was found in X.Org Server before xorg-x11-server 1.20.9. An Out-Of-Bounds access in XkbSetNames function may lead to a privilege escalation vulnerability. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

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.

An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Splitting attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the browser cache and any downstream caches with content from an arbitrary source. Squid uses a string search instead of parsing the Transfer-Encoding header to find chunked encoding. This allows an attacker to hide a second request inside Transfer-Encoding: it is interpreted by Squid as chunked and split out into a second request delivered upstream. Squid will then deliver two distinct responses to the client, corrupting any downstream caches.

An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Smuggling attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the proxy cache and any downstream caches with content from an arbitrary source. When configured for relaxed header parsing (the default), Squid relays headers containing whitespace characters to upstream servers. When this occurs as a prefix to a Content-Length header, the frame length specified will be ignored by Squid (allowing for a conflicting length to be used from another Content-Length header) but relayed upstream.

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.

In QEMU through 5.0.0, an integer overflow was found in the SM501 display driver implementation. This flaw occurs in the COPY_AREA macro while handling MMIO write operations through the sm501_2d_engine_write() callback. A local attacker could abuse this flaw to crash the QEMU process in sm501_2d_operation() in hw/display/sm501.c on the host, resulting in a denial of service.

Squid before 4.13 and 5.x before 5.0.4 allows a trusted peer to perform Denial of Service by consuming all available CPU cycles during handling of a crafted Cache Digest response message. This only occurs when cache_peer is used with the cache digests feature. The problem exists because peerDigestHandleReply() livelocking in peer_digest.cc mishandles EOF.

Net-SNMP through 5.7.3 has Improper Privilege Management because SNMP WRITE access to the EXTEND MIB provides the ability to run arbitrary commands as root.