CVE-2021-39228

MEDIUMNVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.5 under NVD CVSS v3. EPSS exploit probability: 0.6%, top 32% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
6.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 1%CVSS: 6.5Exploit: NoneExposed: 0

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

Tremor is an event processing system for unstructured data. A vulnerability exists between versions 0.7.2 and 0.11.6. This vulnerability is a memory safety Issue when using patch or merge on state and assign the result back to state. In this case, affected versions of Tremor and the tremor-script crate maintains references to memory that might have been freed already. And these memory regions can be accessed by retrieving the state, e.g. send it over TCP or HTTP. This requires the Tremor server (or any other program using tremor-script) to execute a tremor-script script that uses the mentioned language construct. The issue has been patched in version 0.11.6 by removing the optimization and always cloning the target expression of a Merge or Patch. If an upgrade is not possible, a possible workaround is to avoid the optimization by introducing a temporary variable and not immediately reassigning to state.

CVSS v3
6.5
EG Score
6.5(medium)
EPSS
67.2%
KEV
Not listed

Published

September 17, 2021

Last Modified

November 21, 2024

References (8)

Affected Packages

(1 across 1 ecosystem)
crates.io(1)
PackageVulnerable rangeFixed inDependents
tremor-script—0.11.6—

Weakness Classification(2)

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

Data Freshness Timeline

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2021-39228?
CVE-2021-39228 is a medium vulnerability published on September 17, 2021. Tremor is an event processing system for unstructured data. A vulnerability exists between versions 0.7.2 and 0.11.6. This vulnerability is a memory safety Issue when using patch or merge on state and assign the result back to state. In this case, affected versions of Tremor and the tremor-script…
When was CVE-2021-39228 disclosed?
CVE-2021-39228 was first published in the National Vulnerability Database on September 17, 2021, 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-2021-39228 actively exploited?
CVE-2021-39228 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 67.2% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-39228?
CVE-2021-39228 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2021-39228?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-39228, 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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