CVE-2026-56787

RTKLIB through 2.4.3 contains an off-by-one out-of-bounds read vulnerability in the decode_ssr3 function at src/rtcm3.c:1446 that allows remote attackers to trigger a global buffer overflow via crafted RTCM3 SSR messages with attacker-controlled signal mode fields. Remote attackers can exploit this vulnerability by sending malicious SSR correction streams over NTRIP or serial connections to cause denial of service or crash RTKLIB rovers and CORS servers.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/tomojitakasu/RTKLIB/issues/798	Exploit Issue Tracking Third Party Advisory
https://www.vulncheck.com/advisories/rtklib-off-by-one-out-of-bounds-read-in-decode-ssr3-via-rtcm3-ssr-message	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

26 Jun 2026, 16:53

Type	Values Removed	Values Added
First Time		Rtklib rtklib Rtklib
References	~~() https://github.com/tomojitakasu/RTKLIB/issues/798 -~~	() https://github.com/tomojitakasu/RTKLIB/issues/798 - Exploit, Issue Tracking, Third Party Advisory
References	~~() https://www.vulncheck.com/advisories/rtklib-off-by-one-out-of-bounds-read-in-decode-ssr3-via-rtcm3-ssr-message -~~	() https://www.vulncheck.com/advisories/rtklib-off-by-one-out-of-bounds-read-in-decode-ssr3-via-rtcm3-ssr-message - Third Party Advisory
CPE		cpe:2.3:a:rtklib:rtklib::::::::

25 Jun 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-25 19:16

Updated : 2026-06-26 16:53

NVD link : CVE-2026-56787

Mitre link : CVE-2026-56787

CVE.ORG link : CVE-2026-56787

JSON object : View

Products Affected

rtklib

rtklib

CWE

CWE-193

Off-by-one Error

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