{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-40303","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-04-10T20:22:44.036Z","datePublished":"2026-04-17T21:01:51.899Z","dateUpdated":"2026-04-20T16:19:07.291Z"},"containers":{"cna":{"title":"zrok allows unauthenticated DoS via unbounded memory allocation in striped session cookie parsing","problemTypes":[{"descriptions":[{"cweId":"CWE-400","lang":"en","description":"CWE-400: Uncontrolled Resource Consumption","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-789","lang":"en","description":"CWE-789: Memory Allocation with Excessive Size Value","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"name":"https://github.com/openziti/zrok/security/advisories/GHSA-cpf9-ph2j-ccr9","tags":["x_refsource_CONFIRM"],"url":"https://github.com/openziti/zrok/security/advisories/GHSA-cpf9-ph2j-ccr9"},{"name":"https://github.com/openziti/zrok/releases/tag/v2.0.1","tags":["x_refsource_MISC"],"url":"https://github.com/openziti/zrok/releases/tag/v2.0.1"}],"affected":[{"vendor":"openziti","product":"zrok","versions":[{"version":"< 2.0.1","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-04-17T21:01:51.899Z"},"descriptions":[{"lang":"en","value":"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."}],"source":{"advisory":"GHSA-cpf9-ph2j-ccr9","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-20T16:18:59.334800Z","id":"CVE-2026-40303","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-04-20T16:19:07.291Z"}}]}}