CVE-2026-45740: protobufjs: Denial of Service via unbounded recursive JSON descriptor expansion

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-13 · updated 2026-06-17
Weakness: CWE-674

Description

protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.5.8 and 8.2.0, protobufjs could recurse without a depth limit while expanding nested JSON descriptors through Root.fromJSON() and Namespace.addJSON(). A crafted JSON descriptor with deeply nested namespace definitions could cause the JavaScript call stack to be exhausted during descriptor loading. This vulnerability is fixed in 7.5.8 and 8.2.0.

Affected products

protobufjs: before 7.5.8; from 8.0.0 before 8.2.0 — fixed in 7.5.8, 8.2.0

How to fix

Upgrade to a fixed version: protobufjs 7.5.8, 8.2.0. Check the vendor advisory for mitigations.

References

https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-jggg-4jg4-v7c6

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