CVE-2026-56786

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/tomojitakasu/RTKLIB/issues/799	Exploit Issue Tracking Third Party Advisory
https://www.vulncheck.com/advisories/rtklib-out-of-bounds-write-in-decode-type1033-via-crafted-rtcm3-message	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:rtklib:rtklib:*:*:*:*:*:*:*:*

History

26 Jun 2026, 16:52

Type	Values Removed	Values Added
First Time		Rtklib rtklib Rtklib
CPE		cpe:2.3:a:rtklib:rtklib::::::::
References	~~() https://github.com/tomojitakasu/RTKLIB/issues/799 -~~	() https://github.com/tomojitakasu/RTKLIB/issues/799 - Exploit, Issue Tracking, Third Party Advisory
References	~~() https://www.vulncheck.com/advisories/rtklib-out-of-bounds-write-in-decode-type1033-via-crafted-rtcm3-message -~~	() https://www.vulncheck.com/advisories/rtklib-out-of-bounds-write-in-decode-type1033-via-crafted-rtcm3-message - Third Party Advisory

25 Jun 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-25 19:16

Updated : 2026-06-26 16:52

NVD link : CVE-2026-56786

Mitre link : CVE-2026-56786

CVE.ORG link : CVE-2026-56786

JSON object : View

Products Affected

rtklib

rtklib

CWE

CWE-787

Out-of-bounds Write

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