A vulnerability in the assisted-service REST API, an optional Assisted Installer (assisted-service) component in the Multicluster Engine (MCE), allows an authenticated user with minimal namespace-scoped privileges to obtain administrative credentials for arbitrary clusters provisioned through the hub.

The credentials download endpoint (GET /v2/clusters/{clusterid}/credentials, which returns the kubeadmin password) and the kubeconfig download endpoint are operational in AUTHTYPE=local mode, the only authentication mode available in on-premises ACM/MCE hub deployments. The local authenticator unconditionally grants full administrative access to any request bearing a valid JWT, with no per-endpoint restrictions. A valid local JWT is embedded as a plaintext query parameter in InfraEnvStatus.ISODownloadURL and is readable by any user who has get rights on an InfraEnv object in their own namespace.

The affected components ship as part of Multicluster Engine (MCE). The Red Hat Advanced Cluster Management (ACM) deployments that include MCE are equally affected. This issue does not affect the hosted SaaS offering (console.redhat.com), which uses a different authentication mode.

Successful exploitation gives the attacker the kubeadmin password and kubeconfig for any OpenShift cluster provisioned through the affected hub, granting unrestricted root-level administrative access to those spoke clusters.

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-qr6x-62gq-4ccp. This link is maintained to preserve external references.

Original Description A flaw was found in the Wildfly Server Role Based Access Control (RBAC) provider. When authorization to control management operations is secured using the Role Based Access Control provider, a user without the required privileges can suspend or resume the server. A user with a Monitor or Auditor role is supposed to have only read access permissions and should not be able to suspend the server. The vulnerability is caused by the Suspend and Resume handlers not performing authorization checks to validate whether the current user has the required permissions to proceed with the action.

A flaw was found in libssh in the server-side GSSAPI Curve25519 key exchange path in src/kex-gss.c. In sshservergsskexprocessinit(), a client-controlled SSH string is unpacked into clientpubkey and then copied with memcpy(..., CURVE25519PUBKEYSIZE) without validating sshstringlen(clientpubkey). A remote unauthenticated client can send a short public key in SSHMSGKEXGSSINIT and trigger an out-of-bounds heap read during handshake processing, disclosing small amounts of adjacent server memory.

A flaw was found in Keycloak. An authenticated administrator with the manage-clients role can exploit a Time-of-check to time-of-use (TOCTOU) vulnerability in the name-based admin role checks. This allows the attacker to escalate their privileges to realm-admin for all users within the realm, granting them extensive control over the system. The composite role relationship persists even after the attacker's own permissions are revoked and across system reboots.

A flaw was found in the Keycloak Admin REST API, which is used to manage security realms and clients. The issue occurs when the system processes requests for rotated client secrets that are stored in a secure vault. Due to improper boundary enforcement, a delegated administrator with view-only permissions can retrieve the actual resolved secret instead of the vault placeholder, leading to the exposure of sensitive credentials.

A flaw was found in Keycloak's Fine-Grained Admin Permissions v2 (FGAP v2) implementation. When FGAP v2 is enabled, the role groups endpoints (GET /admin/realms/{realm}/clients/{clientUuid}/roles/{roleName}/groups and GET /admin/realms/{realm}/roles/{roleName}/groups) fail to correctly enforce per-group view permissions. The RoleContainerResource.getGroupsInRole() method only verifies that the caller has permission to view the role itself (auth.roles().requireView(roleContainer)). It then returns representations for all groups mapped to that role without verifying if the caller has permission to view each individual group (auth.groups().canView(group)). This allows a delegated administrator with role view access to enumerate hidden groups and retrieve their metadata, including names, paths, and custom attributes, even if direct access to those groups is correctly denied with a 403 Forbidden error.

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-jhvj-f397-8w6q. This link is maintained to preserve external references.

Original Description A flaw was found in the HAL Console in the Wildfly component, which does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output used as a web page that is served to other users. The attacker must be authenticated as a user that belongs to management groups “SuperUser”, “Admin”, or “Maintainer”.

A flaw was identified in the Account REST API of Keycloak that allows a user authenticated at a lower security level to perform sensitive actions intended only for higher-assurance sessions. Specifically, an attacker who has already obtained a victim’s password can delete the victim’s registered MFA/OTP credential without first proving possession of that factor. The attacker can then register their own MFA device, effectively taking full control of the account. This weakness undermines the intended protection provided by multi-factor authentication.

A flaw was found in GNU tar. The --one-top-level option is intended to confine extraction under a designated directory, but hardlink targets from the archive are not confined the same way and are resolved relative to the extraction working directory (or the directory given with -C). A crafted archive can create hardlinks inside the --one-top-level directory that point to files outside it. If a suitable symbolic link already exists under the extraction working directory, hardlinking to that symlink can bypass tar's usual symlink-based path protections and allow writing outside the intended top-level directory during a single extraction. Users who rely on --one-top-level as a security boundary when extracting untrusted archives may be affected.

A flaw was found in SSSD. The sssnssprotocolparseaddr() function in the NSS responder (src/responder/nss/nssprotocol.c) extracts a 32-bit addrlen value from the client request but only validates that the body is at least 8 bytes, without checking that addrlen fits within the remaining packet body. This unvalidated length is passed through to tallocmemdup() in cachereqdatacreate(), which copies addrlen bytes from the small request buffer, causing a heap-buffer-overflow read. A local attacker can trigger this by connecting to the world-writable NSS responder socket (/var/lib/sss/pipes/nss) and sending a SSSNSSGETHOSTBYADDR (0x0053) request with a large addrlen value and a valid address family payload so that inetntop() succeeds. Successful exploitation crashes the sssdnss responder, causing a denial of service for NSS name resolution. Reported via PSIRTSUPT-20553 by BreachX Zero Day Labs.

A flaw was found in OpenSSH. A local unprivileged attacker on a Linux client host can hijack client-side X11 forwarding connections. This is possible by pre-binding the preferred abstract X socket name when X11 forwarding is enabled and a local UNIX-domain X socket is used. A successful attack can compromise the confidentiality of forwarded X11 traffic, including sensitive window contents and input, and may allow some manipulation of the forwarded session.

A flaw was found in OpenSSH. A malicious SSH server can exploit a double free vulnerability in the Diffie-Hellman Group Exchange (DH-GEX) client path. This occurs during FIPS (Federal Information Processing Standards) mode known-group validation when the client processes attacker-controlled DH-GEX group parameters. Successful exploitation leads to client-side process termination, resulting in a Denial of Service (DoS).

A container privilege escalation flaw was found in certain Ansible Automation Platform images. This issue arises from the /etc/passwd file being created with group-writable permissions during the build process. In certain conditions, an attacker who can execute commands within an affected container, even as a non-root user, can leverage their membership in the root group to modify the /etc/passwd file. This vulnerability allows an attacker to add a new user with any arbitrary UID, including UID 0, gaining full root privileges within the container.

A stack buffer overflow exists in 389 Directory Server's checkPrefix() function (pw.c:440-466). When parsing reversible-encrypted attribute values in the format {SCHEME-<algid>}ciphertext, the algorithm ID is copied into a 256-byte stack buffer via memcpy with no bounds check on (end - delim).

An attacker with Directory Manager privileges can crash ns-slapd by storing a crafted nsDS5ReplicaCredentials (or similar reversible-encrypted config attribute) with an oversized algorithm ID. FORTIFYSOURCE (memcpychk) aborts the process before overflow bytes are written, limiting impact to DoS (SIGABRT) only. Code execution is not possible on production builds.

Production crashes confirmed on RHEL 7 (389-ds-base-1.3.11.1-5.el79) and Fedora 42 (389-ds-base-3.1.4-6.fc42). RHEL 8 crash confirmed via dse.ldif injection (389-ds-base-1.4.3.39-2.moduleel8).

Note: cn=config is local configuration and not replicated; triggering requires Directory Manager access on the target server.

Advisory: 389-ds-campaign-2026-04/003-Stack-Overflow-checkPrefix/advisory.md. Source: PSIRTSUPT-7600 (Ian Murphy, Red Hat Product Security).

A flaw was found in libssh channel handling. In sshpacketchannelopen() in src/messages.c and sshpacketchannelopenconf() in src/channels.c, the implementation accepts a peer-controlled maximum packet size of 0 in channel open messages. That zero value is stored in channel state and later reaches channelwritecommon(), where forward progress depends on the remote maximum packet size being positive; with 0, the remaining length is never reduced and the write path loops indefinitely, consuming CPU and causing denial of service. A remote authenticated peer can trigger this by advertising a zero maximum packet size in SSHMSGCHANNELOPEN or SSHMSGCHANNELOPENCONFIRMATION.

A flaw was found in libssh client-side ProxyCommand handling. In sshsocketconnectproxycommand() in src/socket.c, the return value of fork() was not checked before being stored as the proxy child PID. If fork() fails, the value -1 can be retained in state and later used during cleanup, causing signals to be sent across the caller's accessible process tree. In deployments that use ProxyCommand, this can lead to local denial of service.

A flaw was found in libssh server-side SFTP request handling. In sftpmakeclientmessage() and the downstream processread() path in src/sftpserver.c, the implementation accepts a client-controlled SSHFXPREAD length without enforcing a reasonable upper bound. The parsed len field later drives memory allocation in the SFTP server read path, so a remote authenticated client can request an excessively large read length and force the server to allocate excessive memory. Repeated requests can exhaust available memory and lead to denial of service.

A flaw was found in libssh client-side SFTP message handling. In sftpgetmessage() in src/sftpcommon.c, SFTP responses carrying unknown request IDs were accepted and kept queued instead of being rejected. A malicious SFTP server can repeatedly send responses for request IDs that were never issued by the client, causing unbounded growth of queued messages and leading to client-side memory exhaustion and denial of service.

A flaw was found in GStreamer gst-plugins-good (avidemux). In gstavidemuxriffparsevprp(), the number of available gstriffvprpvideofielddesc entries is calculated by dividing the remaining buffer size by the attacker-controlled vprp->fields value, rather than by sizeof(gstriffvprpvideofielddesc). This can cause the parser to treat more field descriptors as available than fit in the input buffer, resulting in out-of-bounds reads. Processing a crafted AVI via playbin/decodebin can crash the application (denial of service). Fixed upstream in gst-plugins-good 1.28.6 (GStreamer-SA-2026-0072).

A flaw was found in GStreamer gst-plugins-good (avidemux). When parsing FUJIFILM metadata in an AVI strd chunk, gstavidemuxparsestrd() decrements a remaining-length counter by fixed offsets (98 and 10 bytes) without verifying sufficient data remains. For crafted strd payloads of exactly 106 or 107 bytes, the counter underflows to a very large unsigned value, causing subsequent null-terminated string scanning to read far beyond the allocated heap buffer. Date-format normalization may also write beyond the buffer end. Confirmed impacts include heap out-of-bounds read, out-of-bounds write, heap information disclosure (adjacent data appearing in parsed metadata), and application crash/denial of service. The avidemux element is auto-plugged by playbin, decodebin, and gst-discoverer, so opening or previewing a crafted AVI is sufficient to trigger the issue. Fixed upstream in gst-plugins-good 1.28.6 (GStreamer-SA-2026-0072).

A flaw was found in Red Hat Quay's Proxy Cache configuration feature. When an organization administrator configures an upstream registry for proxy caching, Quay makes a network connection to the specified registry hostname without verifying that it points to a legitimate external service. An attacker with organization administrator privileges could supply a crafted hostname to force the Quay server to make requests to internal network services, cloud infrastructure endpoints, or other resources that should not be accessible from the Quay application.

A flaw was found in Red Hat Quay and mirror registry for Red Hat OpenShift. The log export feature in these products allows an authenticated user to specify an arbitrary callback URL. A backend process then makes server-side HTTP requests to this provided URL. This vulnerability, known as Server-Side Request Forgery (SSRF), could allow an attacker to send requests from the application's internal network, potentially leading to the disclosure of sensitive information.

By using a specially crafted HTTP request, the authentication of the jmx-console can be bypassed, as the access restrictions only apply for GET and POST.

Current setting is:

<security-constraint> <web-resource-collection> <web-resource-name>HtmlAdaptor</web-resource-name> <description>An example security config that only allows users with the role JBossAdmin to access the HTML JMX console web application </description> <url-pattern>/</url-pattern> <http-method>GET</http-method> <http-method>POST</http-method> </web-resource-collection> <auth-constraint> <role-name>JBossAdmin</role-name> </auth-constraint> </security-constraint>

and should be changed to block ALL http-methods.

Acknowledgements:

Red Hat would like to thank Stefano Di Paola and Giorgio Fedon of Minded Security for responsibly reporting this issue.

A flaw was found in p11-kit. The RPC message attribute parsing functions p11rpcmessagegetattribute() and p11rpcmessagegetattributearrayvalue() form a mutually-recursive call chain with no recursion depth limit when processing nested CKAWRAPTEMPLATE, CKAUNWRAPTEMPLATE, and CKADERIVETEMPLATE attributes. An unauthenticated attacker with local access to the p11-kit RPC Unix domain socket can send a specially crafted request with deeply nested template attributes, causing stack exhaustion and crashing the p11-kit server process and its dependent services.

A TOCTOU (Time-of-Check Time-of-Use) vulnerability in GNU tar's incremental dumpdir 'X' rename handling allows a local attacker with write access to a directory being backed up to influence the restore process if the attacker has access to the system where the restore is being performed. During restoration, files or directories may be created, renamed or overwritten outside the intended extraction directory. This could lead to unauthorized file modification or, in some cases, privilege escalation. Exploitation does not require the attacker to modify or craft the archive, and standard backup and restore workflows—including extracting into a newly created directory without using the -P option do not mitigate the issue.

A vulnerability has been identified in the libarchive library. This flaw involves an integer overflow that can be triggered when processing a Web Archive (WARC) file that claims to have more than INT64MAX - 4 content bytes. An attacker could craft a malicious WARC archive to induce this overflow, potentially leading to unpredictable program behavior, memory corruption, or a denial-of-service condition within applications that process such archives using libarchive. This bug affects libarchive versions prior to 3.8.0.

A vulnerability has been identified in the libarchive library. This flaw involves an 'off-by-one' miscalculation when handling prefixes and suffixes for file names. This can lead to a 1-byte write overflow. While seemingly small, such an overflow can corrupt adjacent memory, leading to unpredictable program behavior, crashes, or in specific circumstances, could be leveraged as a building block for more sophisticated exploitation. This bug affects libarchive versions prior to 3.8.0.

A vulnerability has been identified in the libarchive library. This flaw can be triggered when file streams are piped into bsdtar, potentially allowing for reading past the end of the file. This out-of-bounds read can lead to unintended consequences, including unpredictable program behavior, memory corruption, or a denial-of-service condition.

A stack overflow flaw was found when reading a BFS file system. A crafted BFS filesystem may lead to an uncontrolled loop, causing grub2 to crash.

Nbdkit: nbdkit-server: off-by-one error when processing block status may lead to a denial of service