{"id":"CVE-2026-102692","aliases":["EUVD-2026-102945","GHSA-8365-gj33-rgpf"],"status":"published","title":"RIOT: Potential integer overflow in nanocoap Block2 handling leading to out-of-bounds memory access","description":"RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.07, nanocoap accepts oversized CoAP Block2 option values without enforcing the 20-bit maximum block number, allowing block offset multiplication to overflow on 32-bit targets. The affected master baseline is commit aeeae69e; the verified fix is later on master and remains unreleased. The oversized value passes from coap_get_blockopt() to coap_block_slicer_init(). A remote CoAP client can send a malformed Block2 option that produces an invalid slice range and can cause out-of-bounds memory access, denial of service, or memory corruption. This vulnerability is fixed in 2026.07.","severity":{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.0035,"percentile":0.29098,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-190","CWE-787"],"published":"2026-10-16T16:48:35Z","modified":"2026-11-06T10:46:30Z","products":[{"vendor":"riot-os","product":"riot"}],"references":[{"url":"https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-8365-gj33-rgpf","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/RIOT-OS/RIOT/commit/6b283ace3565d931b3edff7e115d4f79339253b8","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/RIOT-OS/RIOT/commit/ee1fa0ef91874494823d476392572aeefdbc6b74","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/RIOT-OS/RIOT/releases/tag/2026.07","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102692.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102692","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-102692","title":"RIOT: Potential integer overflow in nanocoap Block2 handling leading to out-of-bounds memory access","description":"RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.07, nanocoap accepts oversized CoAP Block2 option values without enforcing the 20-bit maximum block number, allowing block offset multiplication to overflow on 32-bit targets. The affected master baseline is commit aeeae69e; the verified fix is later on master and remains unreleased. The oversized value passes from coap_get_blockopt() to coap_block_slicer_init(). A remote CoAP client can send a malformed Block2 option that produces an invalid slice range and can cause out-of-bounds memory access, denial of service, or memory corruption. This vulnerability is fixed in 2026.07.","status":"published","published":"2026-10-16T16:48:35.776Z","modified":"2026-10-16T21:20:02.887Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-190","CWE-787"],"updated_at":"2026-11-02T13:38:54.394896Z"}],"euvd":[{"id":"EUVD-2026-102945","description":"RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.07, nanocoap accepts oversized CoAP Block2 option values without enforcing the 20-bit maximum block number, allowing block offset multiplication to overflow on 32-bit targets. The affected master baseline is commit aeeae69e; the verified fix is later on master and remains unreleased. The oversized value passes from coap_get_blockopt() to coap_block_slicer_init(). A remote CoAP client can send a malformed Block2 option that produces an invalid slice range and can cause out-of-bounds memory access, denial of service, or memory corruption. This vulnerability is fixed in 2026.07.","status":"published","published":"2026-10-16T16:48:35Z","modified":"2026-10-16T21:20:02Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T17:00:01.37578Z"}],"nvd":[{"id":"CVE-2026-102692","description":"RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.07, nanocoap accepts oversized CoAP Block2 option values without enforcing the 20-bit maximum block number, allowing block offset multiplication to overflow on 32-bit targets. The affected master baseline is commit aeeae69e; the verified fix is later on master and remains unreleased. The oversized value passes from coap_get_blockopt() to coap_block_slicer_init(). A remote CoAP client can send a malformed Block2 option that produces an invalid slice range and can cause out-of-bounds memory access, denial of service, or memory corruption. This vulnerability is fixed in 2026.07.","status":"published","published":"2026-10-16T17:17:16.98Z","modified":"2026-10-16T22:17:08.8Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","level":"critical","assessor":"secondary"}],"cwes":["CWE-190","CWE-787"],"updated_at":"2026-11-02T14:13:00.123071Z"}],"osv":[{"id":"CVE-2026-102692","title":"RIOT: Potential integer overflow in nanocoap Block2 handling leading to out-of-bounds memory access","description":"RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.07, nanocoap accepts oversized CoAP Block2 option values without enforcing the 20-bit maximum block number, allowing block offset multiplication to overflow on 32-bit targets. The affected master baseline is commit aeeae69e; the verified fix is later on master and remains unreleased. The oversized value passes from coap_get_blockopt() to coap_block_slicer_init(). A remote CoAP client can send a malformed Block2 option that produces an invalid slice range and can cause out-of-bounds memory access, denial of service, or memory corruption. This vulnerability is fixed in 2026.07.","status":"published","published":"2026-10-16T16:48:35.776Z","modified":"2026-11-07T07:05:06.314042522Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","level":"critical"}],"cwes":["CWE-190","CWE-787"],"updated_at":"2026-11-07T03:07:59.573031Z"}]}}