{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-56786: RTKLIB 2.4.3 - Out-of-bounds Write in decode_type1033 via Crafted RTCM3 Message","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-56786","status":"final","version":"1","initial_release_date":"2026-06-25T18:11:55.232Z","current_release_date":"2026-06-25T18:41:37.413Z","revision_history":[{"date":"2026-06-25T18:11:55.232Z","number":"1","summary":"Initial machine-readable export from HarborGuard."}]},"distribution":{"tlp":{"label":"WHITE"},"text":"Public CVE data; freely redistributable."},"notes":[{"category":"description","text":"RTKLIB through 2.4.3 contains an out-of-bounds write vulnerability in decode_type1033 function that fails to clamp length counters to destination buffer size, allowing up to 191-byte overflow into fixed 64-byte descriptor fields. An attacker controlling an NTRIP or serial RTCM3 correction stream can craft a valid CRC-bearing type-1033 message to corrupt adjacent rtcm_t object members, potentially achieving arbitrary code execution or denial of service.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-56786 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-56786"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-56786"},{"category":"external","summary":"Researcher Disclosure","url":"https://github.com/tomojitakasu/RTKLIB/issues/799"},{"category":"external","summary":"vulncheck.com","url":"https://www.vulncheck.com/advisories/rtklib-out-of-bounds-write-in-decode-type1033-via-crafted-rtcm3-message"}]},"product_tree":{"branches":[{"category":"vendor","name":"tomojitakasu","branches":[{"category":"product_name","name":"RTKLIB","branches":[{"category":"product_version_range","name":"<=2.4.3","product":{"name":"tomojitakasu RTKLIB <=2.4.3","product_id":"CSAFPID-1","product_identification_helper":{"cpe":"cpe:2.3:a:tomojitakasu:rtklib:*:*:*:*:*:*:*:*"}}}]}]}]},"vulnerabilities":[{"cve":"CVE-2026-56786","title":"RTKLIB 2.4.3 - Out-of-bounds Write in decode_type1033 via Crafted RTCM3 Message","notes":[{"category":"description","text":"RTKLIB through 2.4.3 contains an out-of-bounds write vulnerability in decode_type1033 function that fails to clamp length counters to destination buffer size, allowing up to 191-byte overflow into fixed 64-byte descriptor fields. An attacker controlling an NTRIP or serial RTCM3 correction stream can craft a valid CRC-bearing type-1033 message to corrupt adjacent rtcm_t object members, potentially achieving arbitrary code execution or denial of service.","title":"CVE description"}],"product_status":{"known_affected":["CSAFPID-1"]},"scores":[{"cvss_v4":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","baseScore":9.3,"baseSeverity":"CRITICAL"},"products":["CSAFPID-1"]}],"remediations":[{"category":"none_available","details":"No fixed version is published yet. Monitor the upstream advisory.","product_ids":["CSAFPID-1"]}]}]}