When gRPC HTTP2 stack raised a header size exceeded error, it skipped parsing the rest of the HPACK frame. This caused any HPACK table mutations to also be skipped, resulting in a desynchronization of HPACK tables between sender and receiver. If leveraged, say, between a proxy and a backend, this could lead to requests from the proxy being interpreted as containing headers from different proxy clients - leading to an information leak that can be used for privilege escalation or data exfiltration. We recommend upgrading beyond the commit contained in https://github.com/grpc/grpc/pull/33005 https://github.com/grpc/grpc/pull/33005

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - When gRPC HTTP2 stack raised a header size exceeded error, it skipped parsing the rest of the HPACK frame.
    This caused any HPACK table mutations to also be skipped, resulting in a desynchronization of HPACK tables     between sender and receiver. If leveraged, say, between a proxy and a backend, this could lead to requests     from the proxy being interpreted as containing headers from different proxy clients - leading to an     information leak that can be used for privilege escalation or data exfiltration. We recommend upgrading     beyond the commit contained in https://github.com/grpc/grpc/pull/33005     https://github.com/grpc/grpc/pull/33005 (CVE-2023-32731)

Note that Nessus relies on the presence of the package as reported by the vendor.

The remote Redhat Enterprise Linux 9 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2024:10761 advisory.

    Python-based worker for Red Hat connect, used to launch Ansible playbooks via Ansible Runner.

    Security Fix(es):

    * python-wheel: remote attackers can cause denial of service via attacker controlled input to wheel cli     (CVE-2022-40898)

    * gRPC: sensitive information disclosure (CVE-2023-32731)

    * gRPC: Reachable Assertion (CVE-2023-1428)

    * gRPC: hpack table accounting errors can lead to denial of service (CVE-2023-33953)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2024:0573-1 advisory.

  - When gRPC HTTP2 stack raised a header size exceeded error, it skipped parsing the rest of the HPACK frame.
    This caused any HPACK table mutations to also be skipped, resulting in a desynchronization of HPACK tables     between sender and receiver. If leveraged, say, between a proxy and a backend, this could lead to requests     from the proxy being interpreted as containing headers from different proxy clients - leading to an     information leak that can be used for privilege escalation or data exfiltration. We recommend upgrading     beyond the commit contained in https://github.com/grpc/grpc/pull/33005     https://github.com/grpc/grpc/pull/33005 (CVE-2023-32731)

  - gRPC contains a vulnerability whereby a client can cause a termination of connection between a HTTP2 proxy     and a gRPC server: a base64 encoding error for `-bin` suffixed headers will result in a disconnection by     the gRPC server, but is typically allowed by HTTP2 proxies. We recommend upgrading beyond the commit in     https://github.com/grpc/grpc/pull/32309 https://www.google.com/url (CVE-2023-32732)

  - gRPC contains a vulnerability that allows hpack table accounting errors could lead to unwanted disconnects     between clients and servers in exceptional cases/ Three vectors were found that allow the following DOS     attacks: - Unbounded memory buffering in the HPACK parser - Unbounded CPU consumption in the HPACK parser     The unbounded CPU consumption is down to a copy that occurred per-input-block in the parser, and because     that could be unbounded due to the memory copy bug we end up with an O(n^2) parsing loop, with n selected     by the client. The unbounded memory buffering bugs: - The header size limit check was behind the string     reading code, so we needed to first buffer up to a 4 gigabyte string before rejecting it as longer than 8     or 16kb. - HPACK varints have an encoding quirk whereby an infinite number of 0's can be added at the     start of an integer. gRPC's hpack parser needed to read all of them before concluding a parse. - gRPC's     metadata overflow check was performed per frame, so that the following sequence of frames could cause     infinite buffering: HEADERS: containing a: 1 CONTINUATION: containing a: 2 CONTINUATION: containing a: 3     etc (CVE-2023-33953)

  - The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation     can reset many streams quickly, as exploited in the wild in August through October 2023. (CVE-2023-44487)

  - Lack of error handling in the TCP server in Google's gRPC starting version 1.23 on posix-compatible     platforms (ex. Linux) allows an attacker to cause a denial of service by initiating a significant number     of connections with the server. Note that gRPC C++ Python, and Ruby are affected, but gRPC Java, and Go     are NOT affected. (CVE-2023-4785)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2023-282 advisory.

    2023-10-12: CVE-2023-4785 was added to this advisory.

    When gRPC HTTP2 stack raised a header size exceeded error, it skipped parsing the rest of the HPACK frame.
    This caused any HPACK table mutations to also be skipped, resulting in a desynchronization of HPACK tables     between sender and receiver. If leveraged, say, between a proxy and a backend, this could lead to requests     from the proxy being interpreted as containing headers from different proxy clients - leading to an     information leak that can be used for privilege escalation or data exfiltration. We recommend upgrading     beyond the commit contained in  https://github.com/grpc/grpc/pull/33005     https://github.com/grpc/grpc/pull/33005 (CVE-2023-32731)

    gRPC contains a vulnerability whereby a client can cause a termination of connection between a HTTP2 proxy     and a gRPC server: a base64 encoding error for `-bin` suffixed headers will result in a disconnection by     the gRPC server, but is typically allowed by HTTP2 proxies. We recommend upgrading beyond the commit in     https://github.com/grpc/grpc/pull/32309 https://www.google.com/url (CVE-2023-32732)

    Lack of error handling in the TCP server in Google's gRPC starting version 1.23 on posix-compatible     platforms (ex. Linux) allows an attacker to cause a denial of service by initiating a significant number     of connections with the server. Note that gRPC C++ Python, and Ruby are affected, but gRPC Java, and Go     are NOT affected. (CVE-2023-4785)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
258569	Linux Distros Unpatched Vulnerability : CVE-2023-32731	Nessus	Misc.	high
212043	RHEL 9 : rhc-worker-playbook (RHSA-2024:10761)	Nessus	Red Hat Local Security Checks	critical
190881	SUSE SLED15 / SLES15 / openSUSE 15 Security Update : abseil-cpp, grpc, opencensus-proto, protobuf, python-abseil, python-grpcio, re2 (SUSE-SU-2024:0573-1)	Nessus	SuSE Local Security Checks	high
179767	Amazon Linux 2023 : grpc, grpc-cpp, grpc-data (ALAS2023-2023-282)	Nessus	Amazon Linux Local Security Checks	critical

Detections

Analytics

CVE-2023-32731

high

Tenable Plugins

high

critical

high

critical