CVE-2022-39254

HIGHNVD 8.68.6—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.6 under NVD CVSS v3. EPSS exploit probability: 0.2%, top 52% 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
8.6
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 8.6Exploit: NoneExposed: 0

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

matrix-nio is a Python Matrix client library, designed according to sans I/O principles. Prior to version 0.20, when a users requests a room key from their devices, the software correctly remember the request. Once they receive a forwarded room key, they accept it without checking who the room key came from. This allows homeservers to try to insert room keys of questionable validity, potentially mounting an impersonation attack. Version 0.20 fixes the issue.

CVSS v3
8.6
EG Score
8.6(medium)
EPSS
42.8%
KEV
Not listed

Published

September 29, 2022

Last Modified

November 21, 2024

References (4)

Affected Packages

(1 across 1 ecosystem)
PyPI(1)
PackageVulnerable rangeFixed inDependents
matrix-nio0.10.0 ... 0.9.0 (33 versions)0.20—

Weakness Classification(2)

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

Data Freshness Timeline

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2022-39254?
CVE-2022-39254 is a high vulnerability published on September 29, 2022. matrix-nio is a Python Matrix client library, designed according to sans I/O principles. Prior to version 0.20, when a users requests a room key from their devices, the software correctly remember the request. Once they receive a forwarded room key, they accept it without checking who the room key…
When was CVE-2022-39254 disclosed?
CVE-2022-39254 was first published in the National Vulnerability Database on September 29, 2022, 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-2022-39254 actively exploited?
CVE-2022-39254 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 42.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2022-39254?
CVE-2022-39254 has a CVSS v3 base score of 8.6 (NVD).
How do I remediate CVE-2022-39254?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2022-39254, 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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