CVE-2026-44292: protobufjs_project protobufjs Prototype Pollution
Vulnerability summary
CVE-2026-44292 is a medium (CVSS 5.3) Prototype Pollution vulnerability in protobufjs_project protobufjs. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 25.4% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 0 · Related 1Timeline
- 13-05-2026PublishedVulnerability first disclosed.
- 18-05-2026Last modifiedVulnerability information updated.
Description
protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.5.6 and 8.0.2, protobufjs generated message constructors copied enumerable properties from a provided properties object without filtering the __proto__ key. If an application constructed a message from an attacker-controlled plain object, an own enumerable __proto__ property could alter the prototype of that individual message instance. This vulnerability is fixed in 7.5.6 and 8.0.2.
CVSS metrics
5 scores · 5 sources · 1 version- OSV · WolfiEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- OSV · NpmEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- OSV · ChainguardEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS trend
Probability
0.34%
Chance of exploitation in the next 30 days
Percentile
25%
Versus all other CVEs
30-day change
+0.07 pp
From 0.26% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Chainguard25 products
- cadence-web< 4.0.15-r2
- gemini-cli< 0.44.0-r0
- homepage< 1.13.1-r3
- kibana-8.19< 8.19.15-r0
- kibana-8.19-bitnami< 8.19.15-r0
Wolfi4 products
- kubeflow-centraldashboard< 1.10.0-r21
- pulumi-language-nodejs< 3.237.0-r1
- renovate< 43.170.15-r2
- vitess-23< 23.0.4-r5
Npm1 product
- protobufjs< 7.5.6 | ≥ 8.0.0, < 8.0.2
Protobufjs1 product
- protobuf.js< 7.5.6 | ≥ 8.0.0, < 8.0.2
Protobufjs_project1 product
- protobufjs< 7.5.6 | ≥ 8.0.0, < 8.0.2
5 vendors · 32 products
References
6 links- github.com/protobufjs/protobuf.js/security/advisories/GHSA-fx83-v9x8-x52wX Refsource CONFIRMAdvisoryWEBMitigationVendor Advisory