CVE-2026-81913
Concrete CMS versions 9.5.0 through 9.5.2 are vulnerable to Open Redirect via the rcURL parameter. An attacker can craft a single link on th
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0-100
Published: Sep 11, 2026 · Last modified: Sep 11, 2026 · CWE-601
Not enough EPSS history yet.
Concrete CMS versions 9.5.0 through 9.5.2 are vulnerable to Open Redirect via the rcURL parameter. An attacker can craft a single link on the site's own domain that sends a user to an arbitrary external site immediately after authentication, facilitating phishing and credential theft. The same handling is present in the registration flow, giving a second entry point on sites with registration enabled. Concrete CMS versions prior to 9.5.0 do not include the rcURL parameter or this allowlist and are not affected. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 5.3 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Michal M. for reporting.
CVECVSSEPSSKEVRExploitTitleMod.
CVE-2026-90453——
———A file-upload handler redirects the authenticated client's browser to a URL taken directly from that same request's Referer header, without validating it against the application's own origin. This allows an authenticated attacker to craft a request that causes another user's browser to be redirected to an arbitrary external destination after completing an upload.7hCVE-2026-540729.3 CRI—
———Authorizer is an open-source, self-hostable authentication and authorization server. Prior to version 2.2.1, the `/authorize` endpoint accepts any `redirect_uri` without validating it against `AllowedOrigins`. When `response_type=token` or `response_type=id_token`, the server appends `access_token`, `id_token`, and `refresh_token` as query parameters and issues a 302 redirect to the attacker-supplied URL. An unauthenticated attacker can obtain the required `client_id` from the public `/graphql?query={meta{client_id}}` endpoint. A partial fix was applied in v2.0.1 to other handlers (`oauth_login`, `verify_email`, `magic_link_login`, `forgot_password`, `invite_members`, `oauth_callback`) but `/authorize` was not included. Version 2.2.1 contains a more complete fix.10hCVE-2026-888878.6 HIG—
——0Renovate is a dependency update automation tool. When listing tags/digests for a container image, Renovate follows pagination links supplied by the remote registry in the HTTP Link header and attaches the registry credentials to the follow-up request without verifying that the pagination URL has the same origin as the original registry. A malicious or compromised container registry can therefore specify a Link header pointing to an attacker-controlled host and receive the credentials Renovate uses for that registry. Exploitation requires that the target has container (Docker) dependencies and is already interacting with the malicious or compromised registry. This is fixed in Renovate 44.11.2 (npm and renovate/renovate images), Mend Renovate CE/EE 15.4.0 and the mend-renovate-enterprise-edition Helm chart 10.4.0; the same-origin check can be disabled with RENOVATE_X_DOCKER_PAGINATION_ALLOW_CROSS_ORIGIN.2dCVE-2026-888828.6 HIG—
——0Renovate is a dependency update automation tool. In versions before 44.11.2 (and Mend Renovate CE/EE images and charts before 15.4.0, and mend-renovate-enterprise-edition helm chart before 10.4.0), when listing new package versions from a NuGet registry Renovate follows pagination URLs supplied by the registry in the HTTP `Link` header without verifying that the target has the same origin as the configured registry. Registry credentials are attached to the request for the 'next' page, so a malicious or compromised NuGet registry can return a `Link` header pointing at an attacker-controlled server and cause Renovate to send the registry credentials to that server. Exploitation requires the remote registry to be malicious or compromised; such a registry would normally already have received the credentials on the initial request, so the issue primarily allows the credentials to be delivered to an additional, attacker-chosen host. The fix restricts pagination to the same origin; the previous behaviour can be re-enabled with the RENOVATE_X_NUGET_PAGINATION_ALLOW_CROSS_ORIGIN option.2dCVE-2026-888818.6 HIG—
——0Renovate, a dependency update tool, follows pagination links supplied by the GitHub server in the HTTP `Link` header when interacting with GitHub.com, GitHub Enterprise Cloud, or GitHub Enterprise Server, and sends the credentials configured for that host to the URL given as the 'next' page. Because the pagination URL is not validated against the host originally contacted, a malicious or compromised GitHub server can return a `Link` header pointing to an attacker-controlled host and cause Renovate to disclose those credentials to it. Exploitation requires that the GitHub server Renovate talks to (as the repository host or as a datasource such as github-releases, github-tags, or git-refs) is already malicious or compromised. The issue is fixed in renovate 44.11.3 (npm and renovate/renovate container images), Mend Renovate CE/EE images and the mend-renovate-ce helm chart 15.4.0, and the mend-renovate-enterprise-edition helm chart 10.4.0. There is no workaround; the pre-existing RENOVATE_X_REBASE_PAGINATION_LINKS option disables the new host check and should only be used with servers that intentionally use different pagination hosts.2dCVE-2026-888808.6 HIG—
——0Renovate before 44.11.3 fails to validate Link header destinations when following GitLab server pagination, allowing malicious servers to redirect credential-bearing requests. Attackers controlling a compromised GitLab server can specify a Link header pointing to attacker-controlled infrastructure to exfiltrate authentication credentials.2d