CVE-2020-9309

HIGHNVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2022-05-24. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
8.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 2%CVSS: 8.8Exploit: NoneExposed: 0

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

Silverstripe CMS through 4.5 can be susceptible to script execution from malicious upload contents under allowed file extensions (for example HTML code in a TXT file). When these files are stored as protected or draft files, the MIME detection can cause browsers to execute the file contents. Uploads stored as protected or draft files are allowed by default for authorised users only, but can also be enabled through custom logic as well as modules such as silverstripe/userforms. Sites using the previously optional silverstripe/mimevalidator module can configure MIME whitelists rather than extension whitelists, and hence prevent this issue. Sites on the Common Web Platform (CWP) use this module by default, and are not affected.

CVSS v3
8.8
EG Score
8.8(medium)
EPSS
76.4%
KEV
Not listed

Published

July 15, 2020

Last Modified

November 21, 2024

References (2)

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
composersilverstripe/cms—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
Packagist(1)
PackageVulnerable rangeFixed inDependents
silverstripe/cms2.4.10 ... 4.5.0-rc2 (226 versions)——

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 47× 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. 2026-07-11 08:25 UTCEPSS rescore
  2. 2026-07-11 08:25 UTCEPSS rescore
  3. 2026-07-09 19:07 UTCEPSS rescore
  4. 2026-07-08 15:12 UTCEPSS rescore
  5. 2026-07-07 13:43 UTCEPSS rescore
  6. 2026-07-06 16:25 UTCEPSS rescore
  7. 2026-07-06 02:21 UTCEPSS rescore
  8. 2026-07-06 02:21 UTCEPSS rescore
  9. 2026-07-05 02:28 UTCEPSS rescore
  10. 2026-07-05 02:28 UTCEPSS rescore
  11. 2026-07-04 06:29 UTCEPSS rescore
  12. 2026-07-04 06:29 UTCEPSS rescore
  13. 2026-07-02 16:57 UTCEPSS rescore
  14. 2026-07-01 15:03 UTCEPSS rescore
  15. 2026-07-01 14:46 UTCOSV refresh
  16. 2026-06-30 23:20 UTCEPSS rescore
  17. 2026-06-30 23:20 UTCEPSS rescore
  18. 2026-06-29 14:04 UTCEPSS rescore
  19. 2026-06-28 14:05 UTCEPSS rescore
  20. 2026-06-28 04:54 UTCEPSS rescore
  21. 2026-06-28 04:54 UTCEPSS rescore
  22. 2026-06-27 03:06 UTCEPSS rescore
  23. 2026-06-27 03:06 UTCEPSS rescore
  24. 2026-06-25 13:48 UTCEPSS rescore
  25. 2026-06-25 13:48 UTCEPSS rescore
Show 56 more
  1. 2026-06-24 14:03 UTCEPSS rescore
  2. 2026-06-24 14:03 UTCEPSS rescore
  3. 2026-06-23 21:31 UTCEPSS rescore
  4. 2026-06-23 21:31 UTCEPSS rescore
  5. 2026-06-22 14:23 UTCEPSS rescore
  6. 2026-06-21 14:54 UTCEPSS rescore
  7. 2026-06-21 14:54 UTCEPSS rescore
  8. 2026-06-21 01:57 UTCEPSS rescore
  9. 2026-06-21 01:57 UTCEPSS rescore
  10. 2026-06-19 19:24 UTCEPSS rescore
  11. 2026-06-19 19:24 UTCEPSS rescore
  12. 2026-06-18 17:51 UTCEPSS rescore
  13. 2026-06-18 17:50 UTCEPSS rescore
  14. 2026-06-17 17:50 UTCEPSS rescore
  15. 2026-06-16 17:50 UTCEPSS rescore
  16. 2026-06-15 17:46 UTCEPSS rescore
  17. 2026-06-14 23:15 UTCEPSS rescore
  18. 2026-06-13 22:58 UTCEPSS rescore
  19. 2026-06-13 22:58 UTCEPSS rescore
  20. 2026-06-13 22:56 UTCOSV refresh
  21. 2026-06-12 23:10 UTCEPSS rescore
  22. 2026-06-12 23:10 UTCEPSS rescore
  23. 2026-06-11 13:58 UTCEPSS rescore
  24. 2026-06-11 13:58 UTCEPSS rescore
  25. 2026-06-10 22:16 UTCEPSS rescore
  26. 2026-06-10 13:20 UTCEPSS rescore
  27. 2026-06-08 14:15 UTCEPSS rescore
  28. 2026-06-07 15:23 UTCEPSS rescore
  29. 2026-06-07 15:23 UTCEPSS rescore
  30. 2026-06-06 13:46 UTCEPSS rescore
  31. 2026-06-06 13:46 UTCEPSS rescore
  32. 2026-06-06 13:46 UTCEPSS rescore
  33. 2026-06-05 22:45 UTCEPSS rescore
  34. 2026-06-05 22:45 UTCEPSS rescore
  35. 2026-06-05 06:08 UTCEPSS rescore
  36. 2026-06-05 06:08 UTCEPSS rescore
  37. 2026-06-04 13:10 UTCEPSS rescore
  38. 2026-06-04 13:10 UTCEPSS rescore
  39. 2026-06-02 20:11 UTCEPSS rescore
  40. 2026-06-02 20:11 UTCEPSS rescore
  41. 2026-06-01 13:50 UTCEPSS rescore
  42. 2026-05-31 22:29 UTCEPSS rescore
  43. 2026-05-31 22:29 UTCEPSS rescore
  44. 2026-05-31 00:15 UTCEPSS rescore
  45. 2026-05-31 00:15 UTCEPSS rescore
  46. 2026-05-29 13:42 UTCEPSS rescore
  47. 2026-05-28 13:43 UTCEPSS rescore
  48. 2026-05-28 13:43 UTCEPSS rescore
  49. 2026-05-27 13:39 UTCEPSS rescore
  50. 2026-05-27 13:39 UTCEPSS rescore
  51. 2026-05-27 01:05 UTCEG score recompute
  52. 2026-05-27 01:05 UTCGHSA enrichment
  53. 2026-05-26 13:42 UTCEPSS rescore
  54. 2026-05-26 13:42 UTCEPSS rescore
  55. 2026-05-26 07:17 UTCEPSS rescore
  56. 2026-05-26 07:17 UTCEPSS rescore

Related CVEs(same product + same CWE)

Same product

1 shown

composer:silverstripe/cms

Frequently asked(5)

What is CVE-2020-9309?
CVE-2020-9309 is a high vulnerability published on July 15, 2020. Silverstripe CMS through 4.5 can be susceptible to script execution from malicious upload contents under allowed file extensions (for example HTML code in a TXT file). When these files are stored as protected or draft files, the MIME detection can cause browsers to execute the file contents.…
When was CVE-2020-9309 disclosed?
CVE-2020-9309 was first published in the National Vulnerability Database on July 15, 2020, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2020-9309 actively exploited?
CVE-2020-9309 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 76.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2020-9309?
CVE-2020-9309 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2020-9309?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2020-9309, 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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