{"id":"CVE-2023-37459","aliases":["EUVD-2023-41359","GHSA-6648-m23r-hq8c"],"status":"published","title":"Out-of-bounds read when processing a received IPv6 packet","description":"Contiki-NG is an operating system for internet-of-things devices. In versions 4.9 and prior, when a packet is received, the Contiki-NG network stack attempts to start the periodic TCP timer if it is a TCP packet with the SYN flag set. But the implementation does not first verify that a full TCP header has been received. Specifically, the implementation attempts to access the flags field from the TCP buffer in the following conditional expression in the `check_for_tcp_syn` function. For this reason, an attacker can inject a truncated TCP packet, which will lead to an out-of-bound read from the packet buffer. As of time of publication, a patched version is not available. As a workaround, one can apply the changes in Contiki-NG pull request #2510 to patch the system.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00462,"percentile":0.40285,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-125"],"published":"2023-09-15T19:19:30Z","modified":"2026-10-28T02:30:37Z","products":[{"vendor":"contiki-ng","product":"contiki-ng"}],"references":[{"url":"https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-6648-m23r-hq8c","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory","advisory"]},{"url":"https://github.com/contiki-ng/contiki-ng/pull/2510","tags":["x_refsource_MISC","x_transferred","Issue Tracking","Patch","fix"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/37xxx/CVE-2023-37459.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-37459","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2023-37459","title":"Out-of-bounds read when processing a received IPv6 packet","description":"Contiki-NG is an operating system for internet-of-things devices. In versions 4.9 and prior, when a packet is received, the Contiki-NG network stack attempts to start the periodic TCP timer if it is a TCP packet with the SYN flag set. But the implementation does not first verify that a full TCP header has been received. Specifically, the implementation attempts to access the flags field from the TCP buffer in the following conditional expression in the `check_for_tcp_syn` function. For this reason, an attacker can inject a truncated TCP packet, which will lead to an out-of-bound read from the packet buffer. As of time of publication, a patched version is not available. As a workaround, one can apply the changes in Contiki-NG pull request #2510 to patch the system.","status":"published","published":"2023-09-15T19:19:30.232Z","modified":"2024-09-25T18:04:01.248Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T14:35:16.454633Z"}],"euvd":[{"id":"EUVD-2023-41359","description":"Contiki-NG is an operating system for internet-of-things devices. In versions 4.9 and prior, when a packet is received, the Contiki-NG network stack attempts to start the periodic TCP timer if it is a TCP packet with the SYN flag set. But the implementation does not first verify that a full TCP header has been received. Specifically, the implementation attempts to access the flags field from the TCP buffer in the following conditional expression in the `check_for_tcp_syn` function. For this reason, an attacker can inject a truncated TCP packet, which will lead to an out-of-bound read from the packet buffer. As of time of publication, a patched version is not available. As a workaround, one can apply the changes in Contiki-NG pull request #2510 to patch the system.","status":"published","published":"2023-09-15T19:19:30Z","modified":"2024-09-25T18:04:01Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-03T00:28:12.011224Z"}],"nvd":[{"id":"CVE-2023-37459","description":"Contiki-NG is an operating system for internet-of-things devices. In versions 4.9 and prior, when a packet is received, the Contiki-NG network stack attempts to start the periodic TCP timer if it is a TCP packet with the SYN flag set. But the implementation does not first verify that a full TCP header has been received. Specifically, the implementation attempts to access the flags field from the TCP buffer in the following conditional expression in the `check_for_tcp_syn` function. For this reason, an attacker can inject a truncated TCP packet, which will lead to an out-of-bound read from the packet buffer. As of time of publication, a patched version is not available. As a workaround, one can apply the changes in Contiki-NG pull request #2510 to patch the system.","status":"published","published":"2023-09-15T20:15:08.65Z","modified":"2026-06-17T06:08:15.633Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T14:08:29.595868Z"}],"osv":[{"id":"CVE-2023-37459","title":"Out-of-bounds read when processing a received IPv6 packet","description":"Contiki-NG is an operating system for internet-of-things devices. In versions 4.9 and prior, when a packet is received, the Contiki-NG network stack attempts to start the periodic TCP timer if it is a TCP packet with the SYN flag set. But the implementation does not first verify that a full TCP header has been received. Specifically, the implementation attempts to access the flags field from the TCP buffer in the following conditional expression in the `check_for_tcp_syn` function. For this reason, an attacker can inject a truncated TCP packet, which will lead to an out-of-bound read from the packet buffer. As of time of publication, a patched version is not available. As a workaround, one can apply the changes in Contiki-NG pull request #2510 to patch the system.","status":"published","published":"2023-09-15T19:19:30.232Z","modified":"2026-10-28T02:30:37.774828189Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T15:44:32.510144Z"}]}}