{"id":"CVE-2021-3323","aliases":["EUVD-2021-26654"],"status":"published","title":"Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr","description":"Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr. Zephyr versions \u003e= \u003e=2.4.0 contain Integer Underflow (Wrap or Wraparound) (CWE-191). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc","severity":{"version":"3.1","score":8.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00924,"percentile":0.60664,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-191"],"published":"2021-10-12T21:50:16Z","modified":"2026-06-17T04:04:56Z","products":[{"vendor":"zephyrproject","product":"zephyr"},{"vendor":"zephyrproject-rtos","product":"zephyr"}],"references":[{"url":"http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc","tags":["x_refsource_MISC","x_transferred","Exploit","Patch","Third Party Advisory"]}],"sources":{"cve":[{"id":"CVE-2021-3323","title":"Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr","description":"Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr. Zephyr versions \u003e= \u003e=2.4.0 contain Integer Underflow (Wrap or Wraparound) (CWE-191). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc","status":"published","published":"2021-10-12T21:50:16.135Z","modified":"2024-09-16T17:07:54.201Z","cvss":[{"version":"3.1","score":8.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L","level":"high","assessor":"cna"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:33:04.020035Z"}],"euvd":[{"id":"EUVD-2021-26654","description":"Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr. Zephyr versions \u003e= \u003e=2.4.0 contain Integer Underflow (Wrap or Wraparound) (CWE-191). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc","status":"published","published":"2021-10-12T21:50:16Z","modified":"2024-09-16T17:07:54Z","cvss":[{"version":"3.1","score":8.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L","level":"high"}],"updated_at":"2026-11-03T00:55:45.275329Z"}],"nvd":[{"id":"CVE-2021-3323","description":"Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr. Zephyr versions \u003e= \u003e=2.4.0 contain Integer Underflow (Wrap or Wraparound) (CWE-191). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-89j6-qpxf-pfpc","status":"published","published":"2021-10-12T22:15:08.093Z","modified":"2026-06-17T04:04:56.487Z","cvss":[{"version":"3.1","score":8.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L","level":"high","assessor":"secondary"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:06:59.689345Z"}]}}