How severe is CVE-2026-44293?

No CVSS score has been assigned to CVE-2026-44293 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-44293?

CVE-2026-44293 affects the following packages: protobufjs (npm), protobufjs (npm). Ecosystems affected: npm.

How do I fix CVE-2026-44293?

Update protobufjs to 7.5.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-44293 is resolved across your whole dependency graph.

How do I detect CVE-2026-44293 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for protobufjs, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-44293 if there is no patch (or I can't update yet)?

Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Is CVE-2026-44293 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-44293 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-44293?

CVE-2026-44293 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 35th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-44293?

CVE-2026-44293 is classified as Code Injection (CWE-94). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-44293 published, and has it been updated?

CVE-2026-44293 was published on May 13, 2026 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

CVE-2026-44293 — protobufjs

CVE-2026-44293 is a Code Injection vulnerability in protobufjs. A fix is available for protobufjs — see the affected versions and patch details below.

protobufjs: Code injection through bytes field defaults in generated toObject code

Also known asGHSA-66ff-xgx4-vchm

Published

May 13, 2026

Updated

Oct 28, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Nov 9, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-44293.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs35th percentile — riskier than 35% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

2 pkgs affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

6Kother npm packages depend on this — each one inherits the vulnerability until it's patched upstream

protobufjsnpm

123.5Mdownloads / week

Description

Summary

protobufjs generated JavaScript for toObject conversion could include an unsafe expression derived from a schema-controlled bytes field default value. A crafted descriptor with a non-string default value for a bytes field could cause attacker-controlled code to be emitted into the generated conversion function.

Impact

An attacker who can provide or influence a protobuf descriptor may be able to execute arbitrary JavaScript in the context of the process using protobufjs.

This requires the application to load an attacker-controlled schema or descriptor and then convert a message of the affected type with defaults enabled. Applications that only use trusted, application-defined schemas are not directly affected by this issue.

Preconditions

The application must allow an attacker to control or influence a protobuf JSON descriptor or equivalent reflected schema.
The descriptor must define a bytes field with an attacker-controlled default value.
The application must call toObject with defaults enabled for the affected type.

Workarounds

Do not load protobuf schemas or JSON descriptors from untrusted sources with affected versions. If untrusted schemas must be accepted, validate or restrict field options before loading them and run schema processing in an isolated environment.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`protobufjs`	all versions	7.5.6`npm install protobufjs@7.5.6`
📦npm	`protobufjs`	≥ 8.0.0&&< 8.0.2	8.0.2`npm install protobufjs@8.0.2`

Affected Products

1 product · 2 configurations

Application

protobufjsprotobufjs_project

≥ 8.0.0 && < 8.0.2

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for protobufjs, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update protobufjs to 7.5.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-44293 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatImportant

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…

Workaround published by Red Hat

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.

Source: Red Hat security advisory for CVE-2026-44293 (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat Ansible Automation Platform 2.6 for RHEL 9	`automation-platform-ui-0:2.6.10-1.el9ap`	RHSA-2026:34160
Red Hat Enterprise Linux 10	`rh-podman-desktop-0:1.1.1-1.el10_2`	RHSA-2026:37385
Red Hat Ansible Automation Platform 2.6	`ansible-automation-platform-26/gateway-rhel9:1782761510`	RHSA-2026:34374
Red Hat Developer Hub 1.9	`rhdh/rhdh-hub-rhel9:1781187342`	RHSA-2026:26234
Red Hat OpenShift AI 3.4	`rhoai/odh-dashboard-rhel9:1787347991`	RHSA-2026:60520
Red Hat OpenShift AI 3.4	`rhoai/odh-mod-arch-eval-hub-rhel9:1791861214`	RHSA-2026:84734
Red Hat OpenShift Container Platform 4.18	`openshift4/ose-console-rhel9:1787031447`	RHSA-2026:57487
Red Hat OpenShift Container Platform 4.19	`openshift4/ose-console-rhel9:1786486822`	RHSA-2026:54555

Frequently Asked Questions

## Summary protobufjs generated JavaScript for `toObject` conversion could include an unsafe expression derived from a schema-controlled `bytes` field default value. A crafted descriptor with a non-string default value for a `bytes` field could cause attacker-controlled code to be emitted into the generated conversion function. ## Impact An attacker who can provide or influence a protobuf descriptor may be able to execute arbitrary JavaScript in the context of the process using protobufjs. This requires the application to load an attacker-controlled schema or descriptor and then convert a

O3 Security · Impact-Aware SCA

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