CVE-2026-54269 | protobufjs: Schema-derived names can shadow runtime-significant properties

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: 2026-06-22 Last update: 2026-06-24 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-54269 is rated Low Risk (26.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.24%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-54269

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-23 — 0.24% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-54269

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 3.9 1.4 [email protected]

Weakness enumeration for CVE-2026-54269

GitHub Security Advisory for CVE-2026-54269

GHSA-f38q-mgvj-vph7 · Severity: medium · Ecosystem: npm — protobufjs : Schema-derived names can shadow runtime-significant properties

Affected software / configurations for CVE-2026-54269

Vendor Product Version Raw CPE
protobufjs_project protobufjs < 7.6.3 cpe:2.3:a:protobufjs_project:protobufjs:*:*:*:*:*:node.js:*:*
protobufjs_project protobufjs >= 8.0.0, < 8.6.0 cpe:2.3:a:protobufjs_project:protobufjs:*:*:*:*:*:node.js:*:*
protobufjs_project protobufjs-cli < 1.3.3 cpe:2.3:a:protobufjs_project:protobufjs-cli:*:*:*:*:*:node.js:*:*
protobufjs_project protobufjs-cli >= 2.0.0, < 2.5.1 cpe:2.3:a:protobufjs_project:protobufjs-cli:*:*:*:*:*:node.js:*:*

References for CVE-2026-54269

cvelogic Threat Intelligence