Cyber Resilience

CVE-2026-44288

Protobufjs Project Protobufjs ≤ 7.5.6

Published
13 May 2026
Modified
17 June 2026
Patch / advisory
View advisory
CVSS Score v3.1 5.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS Score 0.0030 22th percentile
Risk Priority 43 floored blend · peak EPSS

Summary

CVE-2026-44288 is a medium-severity Improper Handling of Unicode Encoding (CWE-176) vulnerability in Protobufjs Project Protobufjs. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Invisible Unicode (T1027.018); ranked at the 22th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

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

EU & UK References

Vulnerability Data

protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.5.6 and 8.0.2, protobufjs includes a minimal UTF-8 decoder that accepted overlong UTF-8 byte sequences and decoded them to their canonical characters instead of replacing them. An attacker who can…

more

provide protobuf binary data decoded through the affected UTF-8 path may be able to bypass application-level checks that inspect raw bytes before protobuf string decoding. For example, bytes that do not contain certain ASCII characters could decode to strings containing those characters. This vulnerability is fixed in 7.5.6 and 8.0.2.

CWE(s)
CWE-176

Related Threats

MITRE ATT&CK Enterprise Techniques

T1027.018 Invisible Unicode Stealth
Adversaries may abuse invisible or non-printing Unicode characters to conceal malicious content within files, scripts, or text.
attack.mitre.org →
T1027 Obfuscated Files or Information Stealth
Adversaries may attempt to make an executable or file difficult to discover or analyze by encrypting, encoding, or otherwise obfuscating its contents on the system or in transit.
attack.mitre.org →
T1132 Data Encoding Command And Control
Adversaries may encode data to make the content of command and control traffic more difficult to detect.
attack.mitre.org →
T1132.002 Non-Standard Encoding Command And Control
Adversaries may encode data with a non-standard data encoding system to make the content of command and control traffic more difficult to detect.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-44290Same product: Protobufjs Project Protobufjs
CVE-2026-44292Same product: Protobufjs Project Protobufjs
CVE-2026-59876Same product: Protobufjs Project Protobufjs
CVE-2023-36665Same product: Protobufjs Project Protobufjs
CVE-2026-44294Same product: Protobufjs Project Protobufjs
CVE-2026-41242Same product: Protobufjs Project Protobufjs
CVE-2026-44293Same product: Protobufjs Project Protobufjs
CVE-2026-44291Same product: Protobufjs Project Protobufjs
CVE-2026-44289Same product: Protobufjs Project Protobufjs
CVE-2026-59877Same product: Protobufjs Project Protobufjs

Affected Assets

protobufjs project
protobufjs
≤ 7.5.6 · 8.0.0 — 8.0.2

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SI-10 Information Input Validation good match

Input validation directly requires checking and normalizing encodings so that Unicode is handled consistently before further processing.

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

Secure SDLC practices directly require proper Unicode/input validation to prevent this weakness.

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.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect Unicode-handling flaws before deployment.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle mandates input validation and encoding handling that can prevent Unicode mishandling.

A.8.26 Application security requirements partial match
prevents

Application security requirements include proper handling of character encodings and input sanitization.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles require robust input processing to avoid encoding-related vulnerabilities.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly address proper Unicode and character-encoding validation.

References