CVE-2026-56787

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 75% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.

Triggered by: NVD CVSS baseline
Sources: epss, ghsa, nvd
Trending — 3 sources updated this weekElevated
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.5Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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
7.5
EG Score
7.5(medium)
EG Risk
65(Attend)
EG Risk 65/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS
24.8%
KEV
Not listed

Published

June 25, 2026

Last Modified

July 14, 2026

Advisory Details (2)

Auto-updated Jun 25, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic

RTKLIB 2.4.3 - Off-by-One Out-of-Bounds Read in decode_ssr3 via RTCM3 SSR Message | Advisories | VulnCheck

https://www.vulncheck.com/advisories/rtklib-off-by-one-out-of-bounds-read-in-decode-ssr3-via-rtcm3-ssr-message
generic🟡 PoC Available

Global-Buffer-Overflow in RTKLIB `decode_ssr3` (SSR Code-Bias) via RTCM3 Off-By-One · Issue #798 · tomojitakasu/RTKLIB · GitHub

https://github.com/tomojitakasu/RTKLIB/issues/798

Vendor Advisories for CVE-2026-56787(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 61× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-23 03:20 UTCEG score recompute▲ 1.00
  2. 2026-07-22 14:08 UTCEPSS rescore
  3. 2026-07-20 17:08 UTCEPSS rescore
  4. 2026-07-19 02:29 UTCEPSS rescore
  5. 2026-07-18 10:04 UTCEPSS rescore
  6. 2026-07-16 17:03 UTCEPSS rescore
  7. 2026-07-16 07:08 UTCGHSA enrichment
  8. 2026-07-15 16:57 UTCEPSS rescore
  9. 2026-07-15 16:57 UTCEPSS rescore
  10. 2026-07-15 05:19 UTCGHSA enrichment
  11. 2026-07-15 02:00 UTCEPSS rescore
  12. 2026-07-15 02:00 UTCEPSS rescore
  13. 2026-07-14 23:23 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
  14. 2026-07-14 21:35 UTCMITRE cvelistV5CVSS v3 → 6.5 · severity → MEDIUM
  15. 2026-07-14 03:05 UTCGHSA enrichment
  16. 2026-07-13 22:31 UTCEPSS rescore
  17. 2026-07-13 06:13 UTCEPSS rescore
  18. 2026-07-13 06:13 UTCEPSS rescore
  19. 2026-07-13 01:17 UTCGHSA enrichment
  20. 2026-07-12 05:46 UTCEPSS rescore
  21. 2026-07-11 23:29 UTCGHSA enrichment
  22. 2026-07-11 08:27 UTCEPSS rescore
  23. 2026-07-11 08:27 UTCEPSS rescore
  24. 2026-07-10 21:41 UTCGHSA enrichment
  25. 2026-07-09 19:53 UTCGHSA enrichment
Show 36 more
  1. 2026-07-09 19:10 UTCEPSS rescore
  2. 2026-07-09 19:10 UTCEPSS rescore
  3. 2026-07-08 18:03 UTCGHSA enrichment
  4. 2026-07-08 15:16 UTCEPSS rescore
  5. 2026-07-08 15:16 UTCEPSS rescore
  6. 2026-07-07 16:15 UTCGHSA enrichment
  7. 2026-07-07 13:46 UTCEPSS rescore
  8. 2026-07-07 13:46 UTCEPSS rescore
  9. 2026-07-06 16:27 UTCEPSS rescore
  10. 2026-07-06 16:27 UTCEPSS rescore
  11. 2026-07-06 14:05 UTCGHSA enrichment
  12. 2026-07-06 02:23 UTCEPSS rescore
  13. 2026-07-06 02:23 UTCEPSS rescore
  14. 2026-07-05 12:12 UTCGHSA enrichment
  15. 2026-07-05 02:31 UTCEPSS rescore
  16. 2026-07-05 02:30 UTCEPSS rescore
  17. 2026-07-04 10:24 UTCGHSA enrichment
  18. 2026-07-04 06:31 UTCEPSS rescore
  19. 2026-07-04 06:31 UTCEPSS rescore
  20. 2026-07-03 08:36 UTCGHSA enrichment
  21. 2026-07-02 06:48 UTCGHSA enrichment
  22. 2026-07-01 15:07 UTCEPSS rescore
  23. 2026-07-01 05:00 UTCGHSA enrichment
  24. 2026-06-30 23:22 UTCEPSS rescore
  25. 2026-06-30 03:12 UTCGHSA enrichment
  26. 2026-06-29 14:06 UTCEPSS rescore
  27. 2026-06-29 01:24 UTCGHSA enrichment
  28. 2026-06-28 14:07 UTCEPSS rescore
  29. 2026-06-28 04:56 UTCEPSS rescore
  30. 2026-06-28 04:56 UTCEPSS rescore
  31. 2026-06-27 23:36 UTCGHSA enrichment
  32. 2026-06-27 03:08 UTCEPSS rescore
  33. 2026-06-26 21:48 UTCGHSA enrichment
  34. 2026-06-26 17:41 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
  35. 2026-06-25 19:49 UTCEG score recompute
  36. 2026-06-25 19:49 UTCNVD updatefirst tracked

Frequently asked(5)

What is CVE-2026-56787?
CVE-2026-56787 is a high vulnerability published on June 25, 2026. 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…
When was CVE-2026-56787 disclosed?
CVE-2026-56787 was first published in the National Vulnerability Database on June 25, 2026, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56787 actively exploited?
CVE-2026-56787 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 24.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-56787?
CVE-2026-56787 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-56787?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56787, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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