CVE-2026-56787

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.6%, top 54% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.

Triggered by: NVD CVSS baseline
Sources: epss, ghsa, nvd
Elevated
7.5EG
EchelonGraph verdictPlan mitigationSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 7.5Exploit: Elevated riskExposed services: Not assessed

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

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
7.5HIGHmedium confidence
EG Risk
65
EG Risk 65/100

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%
EPSS PROB
0.6%
EPSS %ILE
45th
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 fix on record 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.

Affected Packages

(3 across 3 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
rtklib2.4.3+dfsg1-2.1 ... 2.4.3.b34+dfsg-1 (8 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
rtklib2.4.3.b34+dfsg-1
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
rtklib2.4.3.b34+dfsg-1
  • every version on: no fix on record
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 34× 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.

Showing the most recent 100 of 226 total refreshes for this CVE.

  1. 2026-10-09 20:07 UTCEPSS rescore
  2. 2026-10-08 17:13 UTCEPSS rescore
  3. 2026-10-07 23:48 UTCEPSS rescore
  4. 2026-10-06 15:18 UTCEPSS rescore
  5. 2026-10-05 17:43 UTCEPSS rescore
  6. 2026-10-04 23:22 UTCEPSS rescore
  7. 2026-10-03 14:26 UTCEPSS rescore
  8. 2026-10-02 17:56 UTCEPSS rescore
  9. 2026-10-01 19:50 UTCEPSS rescore
  10. 2026-09-30 15:03 UTCEPSS rescore
  11. 2026-09-29 15:22 UTCEPSS rescore
  12. 2026-09-28 13:51 UTCEPSS rescore
  13. 2026-09-27 13:48 UTCEPSS rescore
  14. 2026-09-26 15:59 UTCEPSS rescore
  15. 2026-09-24 14:04 UTCEPSS rescore
  16. 2026-09-23 17:54 UTCEPSS rescore
  17. 2026-09-23 08:29 UTCEG score recompute
  18. 2026-09-23 08:29 UTCGHSA enrichment
  19. 2026-09-20 20:16 UTCEPSS rescore
  20. 2026-09-18 19:28 UTCEPSS rescore
  21. 2026-09-18 07:20 UTCEG score recompute
  22. 2026-09-18 07:20 UTCGHSA enrichment
  23. 2026-09-17 19:31 UTCEPSS rescore
  24. 2026-09-16 14:08 UTCEPSS rescore
  25. 2026-09-16 05:15 UTCEPSS rescore
Show 75 more
  1. 2026-09-15 03:11 UTCEPSS rescore
  2. 2026-09-14 01:17 UTCEG score recompute
  3. 2026-09-14 01:17 UTCGHSA enrichment
  4. 2026-09-13 16:47 UTCEPSS rescore
  5. 2026-09-13 09:37 UTCGHSA enrichment
  6. 2026-09-12 15:43 UTCEG score recompute
  7. 2026-09-12 15:43 UTCGHSA enrichment
  8. 2026-09-11 14:53 UTCEPSS rescore
  9. 2026-09-10 09:35 UTCEPSS rescore
  10. 2026-09-08 22:01 UTCEPSS rescore
  11. 2026-09-07 16:01 UTCEPSS rescore
  12. 2026-09-06 13:47 UTCEPSS rescore
  13. 2026-09-04 05:07 UTCEPSS rescore
  14. 2026-09-02 14:12 UTCEPSS rescore
  15. 2026-09-01 13:54 UTCEPSS rescore
  16. 2026-09-01 04:40 UTCEPSS rescore
  17. 2026-08-30 19:31 UTCEG score recompute
  18. 2026-08-30 19:31 UTCGHSA enrichment
  19. 2026-08-30 19:17 UTCEPSS rescore
  20. 2026-08-30 01:22 UTCEPSS rescore
  21. 2026-08-28 21:42 UTCEPSS rescore
  22. 2026-08-27 23:17 UTCEG score recompute
  23. 2026-08-27 23:17 UTCGHSA enrichment
  24. 2026-08-27 14:25 UTCEPSS rescore
  25. 2026-08-26 14:46 UTCEPSS rescore
  26. 2026-08-25 13:49 UTCEPSS rescore
  27. 2026-08-25 01:40 UTCEG score recompute
  28. 2026-08-25 01:40 UTCGHSA enrichment
  29. 2026-08-24 13:09 UTCEG score recompute
  30. 2026-08-24 13:09 UTCGHSA enrichment
  31. 2026-08-23 23:34 UTCGHSA enrichment
  32. 2026-08-23 11:03 UTCEG score recompute
  33. 2026-08-23 11:03 UTCGHSA enrichment
  34. 2026-08-23 00:19 UTCEPSS rescore
  35. 2026-08-22 22:33 UTCGHSA enrichment
  36. 2026-08-22 10:01 UTCEG score recompute
  37. 2026-08-22 10:01 UTCGHSA enrichment
  38. 2026-08-21 23:49 UTCEPSS rescore
  39. 2026-08-21 20:34 UTCGHSA enrichment
  40. 2026-08-21 08:03 UTCEG score recompute
  41. 2026-08-21 08:03 UTCGHSA enrichment
  42. 2026-08-20 22:55 UTCEPSS rescore
  43. 2026-08-20 19:32 UTCGHSA enrichment
  44. 2026-08-20 07:02 UTCEG score recompute
  45. 2026-08-20 07:02 UTCGHSA enrichment
  46. 2026-08-19 17:04 UTCEPSS rescore
  47. 2026-08-19 13:44 UTCGHSA enrichment
  48. 2026-08-19 01:14 UTCEG score recompute
  49. 2026-08-19 01:14 UTCGHSA enrichment
  50. 2026-08-18 13:48 UTCEPSS rescore
  51. 2026-08-17 16:56 UTCEG score recompute
  52. 2026-08-17 16:56 UTCGHSA enrichment
  53. 2026-08-17 13:47 UTCEPSS rescore
  54. 2026-08-17 04:21 UTCGHSA enrichment
  55. 2026-08-16 15:50 UTCEG score recompute
  56. 2026-08-16 15:50 UTCGHSA enrichment
  57. 2026-08-16 14:56 UTCEPSS rescore
  58. 2026-08-16 03:20 UTCEG score recompute
  59. 2026-08-16 03:20 UTCGHSA enrichment
  60. 2026-08-16 02:14 UTCEPSS rescore
  61. 2026-08-15 14:49 UTCGHSA enrichment
  62. 2026-08-15 02:18 UTCEG score recompute
  63. 2026-08-15 02:18 UTCGHSA enrichment
  64. 2026-08-15 01:30 UTCEPSS rescore
  65. 2026-08-14 13:47 UTCGHSA enrichment
  66. 2026-08-14 01:16 UTCEG score recompute
  67. 2026-08-14 01:16 UTCGHSA enrichment
  68. 2026-08-13 22:00 UTCEPSS rescore
  69. 2026-08-13 12:45 UTCGHSA enrichment
  70. 2026-08-13 00:14 UTCEG score recompute
  71. 2026-08-13 00:14 UTCGHSA enrichment
  72. 2026-08-12 13:51 UTCEPSS rescore
  73. 2026-08-12 11:44 UTCGHSA enrichment
  74. 2026-08-11 23:13 UTCEG score recompute
  75. 2026-08-11 23:13 UTCGHSA enrichment

Related CVEs(same product + same CWE)

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 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 0.6% probability of exploitation in the next 30 days (45th percentile of EPSS-scored CVEs).
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?
No fix for CVE-2026-56787 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-56787 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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