CVE-2026-56787
RTKLIB 2.4.3 - Off-by-One Out-of-Bounds Read in decode_ssr3 via RTCM3 SSR Message
Description
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.
INFO
Published Date :
June 25, 2026, 7:16 p.m.
Last Modified :
July 14, 2026, 10:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update RTKLIB to a version that addresses this vulnerability.
- Avoid processing untrusted RTCM3 SSR messages.
- Monitor system stability after applying updates.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-56787.
| URL | 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 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-56787 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-56787
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-56787 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-56787 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
Jul. 14, 2026
Action Type Old Value New Value Changed Affected [{'repo': 'https://github.com/tomojitakasu/RTKLIB', 'vendor': 'tomojitakasu', 'product': 'RTKLIB', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '2.4.3'}], 'defaultStatus': 'unaffected'}] [{'repo': 'https://github.com/tomojitakasu/RTKLIB', 'vendor': 'tomojitakasu', 'product': 'RTKLIB', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '2.4.3'}], 'packageURL': 'pkg:github/tomojitakasu/RTKLIB', 'defaultStatus': 'unaffected'}] -
Initial Analysis by [email protected]
Jun. 26, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:rtklib:rtklib:*:*:*:*:*:*:*:* versions up to (including) 2.4.3 Added Reference Type VulnCheck: https://github.com/tomojitakasu/RTKLIB/issues/798 Types: Exploit, Issue Tracking, Third Party Advisory Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/rtklib-off-by-one-out-of-bounds-read-in-decode-ssr3-via-rtcm3-ssr-message Types: Third Party Advisory -
New CVE Received by [email protected]
Jun. 25, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/tomojitakasu/RTKLIB', 'vendor': 'tomojitakasu', 'product': 'RTKLIB', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '2.4.3'}], 'defaultStatus': 'unaffected'}] Added Description 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L Added CWE CWE-193 Added Reference https://github.com/tomojitakasu/RTKLIB/issues/798 Added Reference https://www.vulncheck.com/advisories/rtklib-off-by-one-out-of-bounds-read-in-decode-ssr3-via-rtcm3-ssr-message -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 25, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-56787', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-25T18:27:10.611620Z'}