CVE-2026-42476

HIGHNVD 7.17.1—
EchelonGraph scoreMEDIUM confidence

Score 7.1 from GitHub Security Advisory (severity: HIGH) published 2026-05-01. NVD baseline CVSS 7.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
7.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.1Exploit: None knownExposed: 0

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

Two heap-based out-of-bounds read vulnerabilities in the STL ASCII file parser in Open CASCADE Technology (OCCT) V8_0_0_rc5 exist in RWStl_Reader::ReadAscii because buffers returned by Standard_ReadLineBuffer::ReadLine() are not properly length-validated before strncasecmp or direct byte access. User-assisted attackers can trigger these issues by persuading a victim to open a crafted STL file with extremely short lines, resulting in a denial of service or possible information disclosure.

CVSS v3
7.1
EG Score
7.1(medium)
EG Risk
32(Track)
EG Risk 32/100SSVC: Track

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
Severity71% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
1%
KEV
Not listed

Published

May 1, 2026

Last Modified

May 1, 2026

Advisory Details (1)

Auto-updated May 1, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

OCCT Multiple Memory Safety Vulnerabilities (CVE-2026-42476 through CVE-2026-42481) · GitHub

https://gist.github.com/sgInnora/dfba083d04906283e9c92aea78e2d94a

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
opencascade7.5.1+dfsg1-2 ... 7.9.2+dfsg-4 (30 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
opencascade7.6.3+dfsg1-7 ... 7.9.2+dfsg-4 (18 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
opencascade7.8.1+dfsg1-3 ... 7.9.2+dfsg-4 (11 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
opencascade7.8.1+dfsg1-3 ... 7.9.2+dfsg-4 (11 versions)——

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 4× in last 7d / 22× 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 164 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-42476?
CVE-2026-42476 is a high vulnerability published on May 1, 2026. Two heap-based out-of-bounds read vulnerabilities in the STL ASCII file parser in Open CASCADE Technology (OCCT) V800rc5 exist in RWStlReader::ReadAscii because buffers returned by Standard_ReadLineBuffer::ReadLine() are not properly length-validated before strncasecmp or direct byte access.…
When was CVE-2026-42476 disclosed?
CVE-2026-42476 was first published in the National Vulnerability Database on May 1, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-42476 actively exploited?
CVE-2026-42476 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 98.8% of all scored CVEs.
What is the CVSS score of CVE-2026-42476?
CVE-2026-42476 has a CVSS v3 base score of 7.1 (NVD).
How do I remediate CVE-2026-42476?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42476, 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.

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