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 56% 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
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 7.5Exploit: Elevated riskExposed: 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 PROB
1%
EPSS %ILE
44%
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.

Affected Packages

(3 across 3 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
rtklib2.4.3+dfsg1-2.1 ... 2.4.3.b34+dfsg-1 (8 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
rtklib2.4.3.b34+dfsg-1——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
rtklib2.4.3.b34+dfsg-1——

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 22× in last 7d / 105× 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 176 total refreshes for this CVE.

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

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 1% probability of exploitation in the next 30 days, which ranks it in the top 55.7% of all 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?
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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