CVE-2026-44293

A flaw was found in protobufjs, a library used to compile protobuf definitions into JavaScript functions. A remote attacker could exploit this vulnerability by providing a crafted descriptor that includes a non-string default value for a bytes field. This could lead to the generation of an unsafe expression within the toObject conversion function, ultimately allowing the attacker to execute arbitrary code.

This is an Important flaw affecting Red Hat products that incorporate the protobufjs library. protobufjs is vulnerable to arbitrary code execution when compiling protobuf definitions into JavaScript. During generation of the toObject conversion function, a schema-controlled default value on a bytes field that is not a string can be emitted as unsafe JavaScript code. An attacker who can supply or influence the protobuf descriptor processed by the application (low privileges required) may achieve code execution in the Node.js process context. Fixed upstream in protobufjs 7.5.6 and 8.0.2. Affects Red Hat offerings that bundle protobufjs and process attacker-influenced protobuf schemas at runtime.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.