Keycloak's device authorization grant does not correctly validate the device code and client ID. An attacker client could abuse the missing validation to spoof a client consent request and trick an authed admin into granting consent to a malicious OAuth client, or possible unauthorized access to an existing OAuth client.
A flaw was found in Keycloak. A Keycloak server configured to support mTLS authentication for OAuth/OpenID clients does not properly verify the client certificate chain. A client that possesses a proper certificate can authorize itself as any other client, therefore, access data that belongs to other clients.
Description An ExecSync request runs a command in a container and returns the output to the Kubelet. It is used for readiness and liveness probes within a pod. The way CRI-O runs ExecSync commands is through conmon. CRI-O asks conmon to start the process, and conmon writes the output to disk. CRI-O then reads the output and returns it to the Kubelet.
If the output of the command is large enough, it is possible to exhaust the memory (or disk usage) of the node. The following deployment is an example yaml file that will output around 8GB of ‘A’ characters, which would be written to disk by conmon and read by CRI-O.
yaml apiVersion: apps/v1 kind: Deployment metadata: name: nginx-deployment100 spec: selector: matchLabels: app: nginx replicas: 2 template: metadata: labels: app: nginx spec: containers: - name: nginx image: nginx:1.14.2 lifecycle: postStart: exec: command: ["/bin/sh", "-c", "seq 1 50000000; do echo -n 'aaaaaaaaaaaaaaaa'; done"]
Impact It is possible for the node to be exhausted of memory or disk space, depending on the node the command is being run on. What is further problematic is that the memory and disk usage aren't attributed to the container, as this file and its processing are implementation details of CRI-O. The consequence of the exhaustion is that other services on the node, e.g. other containers, will be unable to allocate memory and thus causing a denial of service.
Patches This vulnerability will be fixed in 1.24.1, 1.23.3, 1.22.5, v1.21.8, v1.20.8, v1.19.7
Workarounds At the time of writing, no workaround exists other than ensuring only trusted images are used.
References https://github.com/containerd/containerd/security/advisories/GHSA-5ffw-gxpp-mxpf
For more information If you have any questions or comments about this advisory: Open an issue in the CRI-O repo To make a report, email your vulnerability to the private cncf-crio-security@lists.cncf.io list with the security details and the details expected for all CRI-O bug reports.
Credits Disclosed by Ada Logics in a security audit sponsored by CNCF and facilitated by OSTIF.
A flaw was found in Keycloak in the execute-actions-email endpoint. This issue allows arbitrary HTML to be injected into emails sent to Keycloak users and can be misused to perform phishing or other attacks against users.
A crafted JPEG image may lead the JPEG reader to underflow its data pointer, allowing user-controlled data to be written in heap. To a successful to be performed the attacker needs to perform some triage over the heap layout and craft an image with a malicious format and payload. This vulnerability can lead to data corruption and eventual code execution or secure boot circumvention. This flaw affects grub2 versions prior grub-2.12.
A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.