{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-27703", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-02-23T17:56:51.202Z", "datePublished": "2026-03-11T19:38:02.866Z", "dateUpdated": "2026-03-12T19:53:21.857Z" }, "containers": { "cna": { "title": "RIOT has an Out-of-Bounds Write in nanoCoAP Handler", "problemTypes": [ { "descriptions": [ { "cweId": "CWE-787", "lang": "en", "description": "CWE-787: Out-of-bounds Write", "type": "CWE" } ] } ], "metrics": [ { "cvssV3_1": { "attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1" } } ], "references": [ { "name": "https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-qgj4-9jff-93cj", "tags": [ "x_refsource_CONFIRM" ], "url": "https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-qgj4-9jff-93cj" } ], "affected": [ { "vendor": "RIOT-OS", "product": "RIOT", "versions": [ { "version": "<= 2026.01", "status": "affected" } ] } ], "providerMetadata": { "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-03-11T19:38:02.866Z" }, "descriptions": [ { "lang": "en", "value": "RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. In 2026.01 and earlier, the default handler for the well_known_core resource coap_well_known_core_default_handler writes user-provided option data and other data into a fixed size buffer without validating the buffer is large enough to contain the response. This vulnerability allows an attacker to corrupt neighboring stack location, including security-sensitive addresses like the return address, leading to denial of service or arbitrary code execution." } ], "source": { "advisory": "GHSA-qgj4-9jff-93cj", "discovery": "UNKNOWN" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-03-12T19:53:15.324425Z", "id": "CVE-2026-27703", "options": [ { "Exploitation": "poc" }, { "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": "2026-03-12T19:53:21.857Z" } } ] } }