CVE & CISA-KEV Catalog

CVE-2026-40303

HIGH
7.5
CVSS v3
NVD

Description

zrok is software for sharing web services, files, and network resources. Prior to version 2.0.1, endpoints.GetSessionCookie parses an attacker-supplied cookie chunk count and calls make([]string, count) with no upper bound before any token validation occurs. The function is reached on every request to an OAuth-protected proxy share, allowing an unauthenticated remote attacker to trigger gigabyte-scale heap allocations per request, leading to process-level OOM termination or repeated goroutine panics. Both publicProxy and dynamicProxy are affected. Version 2.0.1 patches the issue.

How to fix

Remediation Available
zrokNVD
Affected:< 2.0.1Fixed in:2.0.1CVE-2026-40303derived from NVD

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityNone
IntegrityNone
AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

0.45%probability of exploitation in 30 days
37thpercentile

Low risk: more likely to be exploited than 37% of all known CVEs.

References

Vendor Advisory1
Release Notes1

Related Vulnerabilities

Other CWE-400 (Resource Exhaustion) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2023-44487High7.5100%KEVFix
CVE-2021-44228Critical10.0100%KEV + RansomFix
CVE-2011-3192High7.899%-Fix
CVE-2019-11478Medium5.395%-Fix
CVE-2024-25617Medium5.389%-Fix
CVE-2018-1000115High7.588%-Fix
Embed a live status badge for CVE-2026-40303
CVE-2026-40303 severity badge

Markdown

[![CVE-2026-40303](https://tridentstack.com/cve/badge/CVE-2026-40303.svg)](https://tridentstack.com/cve/CVE-2026-40303)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-40303"><img src="https://tridentstack.com/cve/badge/CVE-2026-40303.svg" alt="CVE-2026-40303"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

See how it worksStart freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-23.