Vulnerability in Rtklib
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L.
EPSS exploit prediction
EPSS: 0.006 (44.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 44.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
- Rtklib
- Tomojitakasu Rtklib — versions 0
Weakness classification (CWE)
References
- github.com/tomojitakasu/RTKLIB/issues/798 (Exploit, technical-description, Third Party Advisory, exploit, Issue Tracking)
- www.vulncheck.com/advisories/rtklib-off-by-one-out-of-bounds-read-in-decode-ssr… (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-56787?
- CVE-2026-56787 is a medium-severity vulnerability in Rtklib, classified under Off-by-one Error. CVSS score: 6.5/10. Published 2026-06-25.
- How severe is CVE-2026-56787?
- Medium severity. CVSS v3 base score is 6.5 out of 10.