Cyber Resilience

CVE-2026-41242

RCE in Protobufjs Project Protobufjs ≤ 7.5.5

Public PoCRCE
Published
18 April 2026
Modified
09 September 2026
Patch / advisory
CVSS Score v4 9.4
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0077 54th percentile
Risk Priority 42 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-41242 is a critical-severity Code Injection (CWE-94) vulnerability in Protobufjs Project Protobufjs. Its CVSS base score is 9.4 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 46% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-41242 is a code injection vulnerability (CWE-94) in the protobufjs library, which compiles Protocol Buffers (protobuf) definitions into JavaScript functions. Versions prior to 8.0.1 and 7.5.5 are affected, allowing attackers to inject arbitrary code into the "type" fields of protobuf definitions. This code executes during object decoding when using the compromised definition, earning a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Remote attackers without authentication or user interaction can exploit this by supplying malicious protobuf definitions to applications using vulnerable protobufjs for decoding. Successful exploitation leads to arbitrary code execution on the target system, potentially resulting in full compromise with high confidentiality, integrity, and availability impacts.

Mitigation requires upgrading to protobufjs version 8.0.1 or 7.5.5, as detailed in the project's security advisory (GHSA-xq3m-2v4x-88gg) and corresponding release notes. Relevant patches are available in commits 535df444ac060243722ac5d672db205e5c531d75 and ff7b2afef8754837cc6dc64c864cd111ab477956.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

protobufjs compiles protobuf definitions into JavaScript (JS) functions. In versions prior to 8.0.1 and 7.5.5, attackers can inject arbitrary code in the "type" fields of protobuf definitions, which will then execute during object decoding using that definition. Versions 8.0.1 and…

more

7.5.5 patch the issue.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1059.002 AppleScript Execution
Adversaries may abuse AppleScript for execution.
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.005 Visual Basic Execution
Adversaries may abuse Visual Basic (VB) for execution.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-44291Same product: Protobufjs Project Protobufjs
CVE-2026-44293Same product: Protobufjs Project Protobufjs
CVE-2023-36665Same product: Protobufjs Project Protobufjs
CVE-2026-54271Same vendor: Protobufjs Project
CVE-2026-44295Same vendor: Protobufjs Project
CVE-2026-66150Shared CWE-94
CVE-2023-49109Shared CWE-94
CVE-2023-6288Shared CWE-94
CVE-2023-33229Shared CWE-94
CVE-2024-9593Shared CWE-94

Affected Assets

protobufjs project
protobufjs
8.0.0 · ≤ 7.5.5

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.3.1

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation finds code paths that accept and execute externally influenced strings.

Input validation directly stops untrusted data from being used to construct executable code without neutralization.

Least privilege limits the damage an injected code fragment can perform once executed.

Requiring documented secure development standards and tools enforces use of safe code-generation APIs and escaping.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly target injection flaws via secure coding and testing (mostly), yet as a single broad outcome it leaves many code-generation specifics unaddressed (partial).

PR.DS-10 none match
prevents

PR.DS-10 protects runtime data confidentiality/integrity but has no bearing on neutralizing externally influenced input during code generation, so neither direction shows any preventive effect.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Banning unapproved code samples and unauthenticated web services, combined with secure-coding standards and SAST, prevents the dynamic generation or inclusion of attacker-supplied code.

References