{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-56789: RTKLIB 2.4.3 - Heap Buffer Overflow and Stack Read via Oversized RINEX Epoch Satellite Count","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-56789","status":"final","version":"1","initial_release_date":"2026-06-25T18:14:05.947Z","current_release_date":"2026-06-25T18:26:36.938Z","revision_history":[{"date":"2026-06-25T18:14:05.947Z","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 a heap buffer overflow vulnerability in the readrnxobsb function in src/rinex.c that allows attackers to trigger memory corruption by failing to clamp satellite count values from RINEX epoch headers. Attackers can craft malicious RINEX files declaring more than 64 satellites per epoch to cause heap buffer overflow writes and out-of-bounds stack reads, crashing RTKLIB-based applications including rnx2rtkp and RTKPOST.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-56789 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-56789"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-56789"},{"category":"external","summary":"Researcher Disclosure","url":"https://github.com/tomojitakasu/RTKLIB/issues/796"},{"category":"external","summary":"vulncheck.com","url":"https://www.vulncheck.com/advisories/rtklib-heap-buffer-overflow-and-stack-read-via-oversized-rinex-epoch-satellite-count"}]},"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-2026-56789","title":"RTKLIB 2.4.3 - Heap Buffer Overflow and Stack Read via Oversized RINEX Epoch Satellite Count","notes":[{"category":"description","text":"RTKLIB through 2.4.3 contains a heap buffer overflow vulnerability in the readrnxobsb function in src/rinex.c that allows attackers to trigger memory corruption by failing to clamp satellite count values from RINEX epoch headers. Attackers can craft malicious RINEX files declaring more than 64 satellites per epoch to cause heap buffer overflow writes and out-of-bounds stack reads, crashing RTKLIB-based applications including rnx2rtkp and RTKPOST.","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:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","baseScore":7.1,"baseSeverity":"HIGH"},"products":["CSAFPID-1"]}],"remediations":[{"category":"none_available","details":"No fixed version is published yet. Monitor the upstream advisory.","product_ids":["CSAFPID-1"]}]}]}