Security Bulletin
Summary
When gRPC encountered an exceeded header size error, it stopped parsing the remainder of the HPACK frame. This also prevented HPACK dynamic table updates from being processed, causing the sender and receiver HPACK tables to fall out of sync. In environments using an HTTP 2 proxy in front of a gRPC backend, an attacker could exploit this desynchronization to have backend servers misinterpret a proxy client's request as containing headers from a different client. This can lead to information disclosure, privilege escalation, or data exfiltration. This could affect watsonx.data.
Vulnerability Details
CVEID: CVE-2023-32731
DESCRIPTION: 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
CWE: CWE-440: Expected Behavior Violation
CVSS Source: IBM X-Force
CVSS Base score: 7.4
CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H)
CVEID: CVE-2023-32732
DESCRIPTION: 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
CWE: CWE-440: Expected Behavior Violation
CVSS Source: IBM X-Force
CVSS Base score: 5.3
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)
Affected Products and Versions
| Affected Product(s) | Version(s) |
| watsonx.data | 2.2.1 |
Remediation/Fixes
The product needs to be installed or upgraded to the latest available level watsonx.data 2.2.2 or watsonx.data on CPD 5.2.2 Installation/upgrade instructions can be found here https://www.ibm.com/docs/en/software-hub/5.2.x?topic=watsonxdata-installing.
Workarounds and Mitigations
None
Get Notified about Future Security Bulletins
References
Acknowledgement
Change History
04 Dec 2025: Initial Publication
*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.
Disclaimer
According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY. In addition to other efforts to address potential vulnerabilities, IBM periodically updates the record of components contained in our product offerings. As part of that effort, if IBM identifies previously unidentified packages in a product/service inventory, we address relevant vulnerabilities regardless of CVE date. Inclusion of an older CVEID does not demonstrate that the referenced product has been used by IBM since that date, nor that IBM was aware of a vulnerability as of that date. We are making clients aware of relevant vulnerabilities as we become aware of them. "Affected Products and Versions" referenced in IBM Security Bulletins are intended to be only products and versions that are supported by IBM and have not passed their end-of-support or warranty date. Thus, failure to reference unsupported or extended-support products and versions in this Security Bulletin does not constitute a determination by IBM that they are unaffected by the vulnerability. Reference to one or more unsupported versions in this Security Bulletin shall not create an obligation for IBM to provide fixes for any unsupported or extended-support products or versions.
Document Location
Worldwide
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Document Information
Modified date:
04 December 2025
Initial Publish date:
04 December 2025
UID
ibm17253733