Vulnerability in Protobufjs Protobuf.js
CVE-2026-54269
protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 8.6.0 and 7.6.3, protobufjs accepted certain schema-derived names that could collide with properties used by protobufjs runtime helpers. The known affected names are fields named hasOwnProperty, field or oneof names such as $type when loaded through protobufjs JSON/reflection descriptors, and service methods whose generated helper name is rpcCall. When affected message or service types were used, protobufjs could read schema-controlled data where it expected an own-property helper, reflected type metadata, or the base RPC helper. This could cause deterministic exceptions or recursive calls in affected decode post-checks, verification, object conversion, reflected JSON serialization, or protobufjs RPC helper invocation. This vulnerability is fixed in 8.6.0 and 7.6.3.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.004 (31.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 31.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Protobufjs Protobuf.js — versions < 7.6.3, >= 8.0.0, < 8.6.0
- Protobufjs Project
- Protobufjs Project Protobufjs-Cli
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-54269?
- CVE-2026-54269 is a medium-severity vulnerability in Protobufjs Protobuf.js, classified under Uncontrolled Recursion. CVSS score: 5.3/10. Published 2026-06-22.
- How severe is CVE-2026-54269?
- Medium severity. CVSS v3 base score is 5.3 out of 10.