Cyber Resilience

CVE-2026-59877

DoS in Protobufjs Project Protobufjs ≤ 7.6.5

Published
08 July 2026
Modified
10 July 2026
Patch / 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:N/A:L
EPSS Score 0.0037 30th percentile
Risk Priority 44 floored blend · peak EPSS

Summary

CVE-2026-59877 is a medium-severity Infinite Loop (CWE-835) vulnerability in Protobufjs Project Protobufjs. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 30th 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 SA-11 (Developer Testing and Evaluation) and SI-2 (Flaw Remediation) — 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 7.6.5 and 8.6.6, protobufjs parsed option names by advancing through schema tokens until reaching an = token without checking for end of input, so a crafted .proto schema that opens…

more

an option declaration and ends prematurely can cause parse, Root.load, or Root.loadSync to loop indefinitely. This issue is fixed in versions 7.6.5 and 8.6.6.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-44289Same product: Protobufjs Project Protobufjs
CVE-2026-48712Same product: Protobufjs Project Protobufjs
CVE-2026-45740Same product: Protobufjs Project Protobufjs
CVE-2026-54270Same product: Protobufjs Project Protobufjs
CVE-2026-44290Same 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-2026-44288Same product: Protobufjs Project Protobufjs
CVE-2026-59876Same product: Protobufjs Project Protobufjs

Affected Assets

protobufjs project
protobufjs
≤ 7.6.5 · 8.0.0 — 8.6.6

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover unreachable loop exit conditions through static analysis, fuzzing, or execution tracing.

Flaw remediation processes identify and correct infinite-loop defects reported from testing or operations.

Requiring documented development processes and secure coding standards reduces introduction of loops whose termination conditions are unreachable.

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 (reviews, testing, static analysis) directly prevent introduction of infinite-loop defects.

ID.RA-01 partial match
prevents

Static analysis and vuln scanning during asset assessment can detect unreachable loop exits.

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.

finds

Security testing can uncover infinite-loop conditions before release.

prevents

Secure development life cycle mandates practices that can detect and prevent infinite-loop defects.

prevents

Application security requirements can specify loop-termination rules, indirectly reducing the weakness.

prevents

Secure coding standards directly address loop termination and prevent infinite loops.

none

Secure architecture principles encourage designs that avoid unreachable exit conditions.

none

Change management can require review of loop logic when code is modified.

References