x/vulndb: potential Go vuln in github.com/rancher/rke2: GHSA-p45j-vfv5-wprq

[GoVulnBot]

In GitHub Security Advisory GHSA-p45j-vfv5-wprq, there is a vulnerability in the following Go packages or modules:

Unit	Fixed	Vulnerable Ranges
github.com/rancher/rke2	1.28.1	>= 1.28.0, < 1.28.1

Cross references:
No existing reports found with this module or alias.

See doc/triage.md for instructions on how to triage this report.

modules:
    - module: github.com/rancher/rke2
      versions:
        - introduced: 1.28.0
          fixed: 1.28.1
      packages:
        - package: github.com/rancher/rke2
    - module: github.com/rancher/rke2
      versions:
        - introduced: 1.27.0
          fixed: 1.27.5
      packages:
        - package: github.com/rancher/rke2
    - module: github.com/rancher/rke2
      versions:
        - introduced: 1.26.0
          fixed: 1.26.8
      packages:
        - package: github.com/rancher/rke2
    - module: github.com/rancher/rke2
      versions:
        - introduced: 1.25.0
          fixed: 1.25.13
      packages:
        - package: github.com/rancher/rke2
    - module: github.com/rancher/rke2
      versions:
        - fixed: 1.24.17
      packages:
        - package: github.com/rancher/rke2
summary: |-
    RKE2 supervisor port is vulnerable to unauthenticated remote denial-of-service
    (DoS) attack via TLS SAN stuffing attack
description: |-
    ### Impact

    An issue was found in RKE2 where an attacker with network access to RKE2
    servers' supervisor port (TCP 9345) can force the TLS server to add entries to
    the certificate's Subject Alternative Name (SAN) list, through a stuffing
    attack, until the certificate grows so large that it exceeds the maximum size
    allowed by TLS client implementations. OpenSSL for example will raise an
    `excessive message size` error when this occurs. No authentication is necessary
    to perform this attack, only the ability to perform a TLS handshake against the
    supervisor port (TCP 9345).

    Affected servers will continue to operate, but clients (server or agent nodes)
    will fail to establish new connections when joining or rejoining the cluster,
    thus leading to a denial of service (DoS) attack.

    ### Remediation

    Upgrade to a fixed release:
    - v1.28.1+rke2r1
    - v1.27.5+rke2r1
    - v1.26.8+rke2r1
    - v1.25.13+rke2r1
    - 1.24.17+rke2r1

    If you are using RKE2 1.27 or earlier, you must also add the parameter
    `tls-san-security: true` to the RKE2 configuration to enable enhanced security
    for the supervisor's TLS SAN list. This option defaults to `true` starting with
    RKE2 1.28.

    Note that this flag changes the behavior of RKE2's supervisor listener. You
    should ensure that you configure `node-external-ip` on servers that will be
    connected to via an external IP, and add `tls-san` entries for any
    load-balancers or VIP addresses that will be associated with the supervisor
    port. External IPs and load-balancer/VIP addresses will no longer be added to
    the supervisor certificate's SAN list unless explicitly configured.

    ### Mitigation

    If you cannot upgrade to a fixed release, the certificate can be "frozen" by
    running the following command against the cluster:

    ```shell kubectl annotate secret -n kube-system rke2-serving
    listener.cattle.io/static=true ```

    **⚠️ IMPORTANT CAUTION:** Note that this mitigation will prevent the
    certificate from adding new SAN entries when servers join the cluster, and
    automatically renewing itself when it is about to expire. If you do this, you
    should delete the annotation when adding new servers to the cluster, or when the
    certificate is within 90 days of expiring, so that it can be updated. Once that
    is done, you can freeze it again.

    Affected certificates can be reset by performing the following steps:
    * Run `kubectl delete secret -n kube-system rke2-serving`
    * Delete `/var/lib/rancher/rke2/server/tls/dynamic-cert.json` from all servers,
    and restart the `rke2-server` service.

    ### Background

    The RKE2 supervisor listens on port TCP 9345 and uses the
    `rancher/dynamiclistener` library to dynamically generate TLS certificates that
    contain TLS Subject Alternative Names (SAN) for any host name or IP address
    requested by a client. This is done to allow servers and external load-balancers
    to be added to the cluster without the administrator having to explicitly know
    and configure in advance a fixed list of endpoints that the supervisor may be
    hosted at.

    The library allows the embedding application to configure a callback that is
    used to filter addresses requested by clients; but this was not previously
    implemented in RKE2.

    ### For more information

    If you have any questions or comments about this advisory:

    - Reach out to the [SUSE Rancher Security
    team](https://github.com/rancher/rke2/security/policy) for security related
    inquiries.
    - Open an issue in the [RKE2](https://github.com/rancher/rke2/issues/new/choose)
    repository.
    - Verify with our [support
    matrix](https://www.suse.com/suse-rancher/support-matrix/all-supported-versions/)
    and [product support lifecycle](https://www.suse.com/lifecycle/).
cves:
    - CVE-2023-32186
ghsas:
    - GHSA-p45j-vfv5-wprq
references:
    - advisory: https://github.com/rancher/rke2/security/advisories/GHSA-p45j-vfv5-wprq
    - advisory: https://github.com/advisories/GHSA-p45j-vfv5-wprq

[gopherbot]

Change https://go.dev/cl/528596 mentions this issue: data/excluded: batch add 10 excluded reports

[gopherbot]

Change https://go.dev/cl/592762 mentions this issue: data/reports: unexclude 75 reports