CVE-2026-9303

MEDIUMNVD 4.34.3—
EchelonGraph scoreMEDIUM confidence

Score 4.3 from GitHub Security Advisory (severity: LOW) published 2026-05-26. NVD baseline CVSS 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 3 sources updated this weekElevated
4.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 4.3Exploit: NoneExposed: 0

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

A vulnerability was identified in calcom cal.diy up to 4.9.4. Impacted is an unknown function. The manipulation leads to cross-site request forgery. It is possible to initiate the attack remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

CVSS v3
4.3
EG Score
4.3(medium)
EG Risk
35(Track)
EG Risk 35/100SSVC: 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
Severity43% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
9.3%
KEV
Not listed

Published

May 23, 2026

Last Modified

July 23, 2026

Advisory Details (2)

Auto-updated Jun 27, 2026
No patch confirmed yet.
generic

Account Takeover via OAuth Account Linking CSRF (Allowlist Bypass) · GitHub

https://gist.github.com/YLChen-007/dafada36e356bc895b09829d8ec57e49
generic

Cross-Site Request Forgery (CSRF) in Calendar Availability API (`/api/availability/calendar`) · GitHub

https://gist.github.com/YLChen-007/26663d9558e15994176dc420d2e11d48

Vendor Advisories for CVE-2026-9303(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 38× 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. 2026-07-23 14:18 UTCEPSS rescore
  2. 2026-07-23 11:51 UTCNVD updateCVSS v4 → 2.1
  3. 2026-07-23 03:23 UTCEG score recompute
  4. 2026-07-22 14:08 UTCEPSS rescore
  5. 2026-07-21 15:25 UTCEPSS rescore
  6. 2026-07-21 15:25 UTCEPSS rescore
  7. 2026-07-20 17:08 UTCEPSS rescore
  8. 2026-07-19 14:31 UTCEPSS rescore
  9. 2026-07-19 02:29 UTCEPSS rescore
  10. 2026-07-18 10:04 UTCEPSS rescore
  11. 2026-07-16 17:03 UTCEPSS rescore
  12. 2026-07-15 16:57 UTCEPSS rescore
  13. 2026-07-15 02:00 UTCEPSS rescore
  14. 2026-07-13 22:31 UTCEPSS rescore
  15. 2026-07-13 06:13 UTCEPSS rescore
  16. 2026-07-12 05:46 UTCEPSS rescore
  17. 2026-07-11 08:27 UTCEPSS rescore
  18. 2026-07-09 19:10 UTCEPSS rescore
  19. 2026-07-08 15:16 UTCEPSS rescore
  20. 2026-07-07 13:46 UTCEPSS rescore
  21. 2026-07-06 16:27 UTCEPSS rescore
  22. 2026-07-06 02:23 UTCEPSS rescore
  23. 2026-07-05 02:31 UTCEPSS rescore
  24. 2026-07-04 06:31 UTCEPSS rescore
  25. 2026-07-04 06:31 UTCEPSS rescore
Show 62 more
  1. 2026-07-01 15:07 UTCEPSS rescore
  2. 2026-06-30 23:22 UTCEPSS rescore
  3. 2026-06-29 14:06 UTCEPSS rescore
  4. 2026-06-29 02:51 UTCGHSA enrichment
  5. 2026-06-28 14:07 UTCEPSS rescore
  6. 2026-06-28 04:56 UTCEPSS rescore
  7. 2026-06-27 19:19 UTCGHSA enrichment
  8. 2026-06-27 03:08 UTCEPSS rescore
  9. 2026-06-26 19:05 UTCGHSA enrichment
  10. 2026-06-25 13:50 UTCGHSA enrichment
  11. 2026-06-25 13:50 UTCEPSS rescore
  12. 2026-06-24 14:05 UTCEPSS rescore
  13. 2026-06-23 21:33 UTCEPSS rescore
  14. 2026-06-22 14:25 UTCEPSS rescore
  15. 2026-06-21 14:56 UTCEPSS rescore
  16. 2026-06-21 01:59 UTCEPSS rescore
  17. 2026-06-19 19:26 UTCEPSS rescore
  18. 2026-06-18 17:52 UTCEPSS rescore
  19. 2026-06-17 21:56 UTCGHSA enrichment
  20. 2026-06-17 17:53 UTCEPSS rescore
  21. 2026-06-16 22:18 UTCGHSA enrichment
  22. 2026-06-16 17:53 UTCEPSS rescore
  23. 2026-06-15 22:43 UTCGHSA enrichment
  24. 2026-06-15 17:49 UTCEPSS rescore
  25. 2026-06-15 17:49 UTCEPSS rescore
  26. 2026-06-14 23:18 UTCEPSS rescore
  27. 2026-06-14 21:22 UTCGHSA enrichment
  28. 2026-06-13 23:00 UTCEPSS rescore
  29. 2026-06-13 21:47 UTCGHSA enrichment
  30. 2026-06-12 23:12 UTCEPSS rescore
  31. 2026-06-12 23:12 UTCEPSS rescore
  32. 2026-06-12 21:37 UTCGHSA enrichment
  33. 2026-06-11 21:56 UTCGHSA enrichment
  34. 2026-06-11 14:00 UTCEPSS rescore
  35. 2026-06-10 22:21 UTCGHSA enrichment
  36. 2026-06-10 22:19 UTCEPSS rescore
  37. 2026-06-10 13:22 UTCEPSS rescore
  38. 2026-06-09 22:46 UTCGHSA enrichment
  39. 2026-06-08 23:11 UTCGHSA enrichment
  40. 2026-06-08 14:17 UTCEPSS rescore
  41. 2026-06-07 23:35 UTCGHSA enrichment
  42. 2026-06-07 15:25 UTCEPSS rescore
  43. 2026-06-07 00:00 UTCGHSA enrichment
  44. 2026-06-06 13:47 UTCEPSS rescore
  45. 2026-06-06 00:24 UTCGHSA enrichment
  46. 2026-06-05 22:47 UTCEPSS rescore
  47. 2026-06-05 00:49 UTCGHSA enrichment
  48. 2026-06-04 13:12 UTCEPSS rescore
  49. 2026-06-04 01:14 UTCGHSA enrichment
  50. 2026-06-03 01:39 UTCGHSA enrichment
  51. 2026-06-02 20:13 UTCEPSS rescore
  52. 2026-06-02 02:03 UTCGHSA enrichment
  53. 2026-06-01 13:52 UTCEPSS rescore
  54. 2026-06-01 02:28 UTCGHSA enrichment
  55. 2026-05-31 22:30 UTCEPSS rescore
  56. 2026-05-31 00:16 UTCEPSS rescore
  57. 2026-05-29 13:44 UTCEPSS rescore
  58. 2026-05-28 13:44 UTCEPSS rescore
  59. 2026-05-27 13:40 UTCEPSS rescore
  60. 2026-05-26 13:44 UTCEPSS rescore
  61. 2026-05-26 07:18 UTCEPSS rescore
  62. 2026-05-23 14:12 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-9303?
CVE-2026-9303 is a medium vulnerability published on May 23, 2026. A vulnerability was identified in calcom cal.diy up to 4.9.4. Impacted is an unknown function. The manipulation leads to cross-site request forgery. It is possible to initiate the attack remotely. The exploit is publicly available and might be used. The vendor was contacted early about this…
When was CVE-2026-9303 disclosed?
CVE-2026-9303 was first published in the National Vulnerability Database on May 23, 2026, with the most recent update on July 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-9303 actively exploited?
CVE-2026-9303 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 9.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-9303?
CVE-2026-9303 has a CVSS v3 base score of 4.3 (NVD).
How do I remediate CVE-2026-9303?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-9303, 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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