CVE-2026-57858

HIGHPre-NVD 8.98.9—
EchelonGraph scoreHIGH confidence

Score 8.9 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-12. a secondary CVSS source baseline 8.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this weekElevated
8.9EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.9Exploit: Elevated riskExposed: 0

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

Cal.com Cal.diy versions 2.1.1 through 6.2.0 contain a stored cross-site scripting vulnerability in the BookingPageTagManager component that allows authenticated event owners to inject arbitrary JavaScript by supplying a malicious analytics tracking ID without sanitization. Attackers can close the inline script string literal with a crafted payload that executes in the browser of every visitor to the affected public booking page, enabling session cookie theft, forged authenticated requests, and wormable propagation by chaining with CSRF-able endpoints to persist payloads on additional events.

CVSS v3
8.9
EG Score
8.9(high)
EG Risk
56(Track*)
EG Risk 56/100SSVC: 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
Severity89% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
0%
EPSS %ILE
35%
KEV
Not listed

Published

August 12, 2026

Last Modified

August 13, 2026

Advisory Details (3)

Auto-updated Aug 12, 2026
No patch confirmed yet.
generic

Cal.com Cal.diy 6.2.0 Stored XSS via BookingPageTagManager Analytics Tracking ID | Advisories | VulnCheck

https://www.vulncheck.com/advisories/cal-com-cal-diy-stored-xss-via-bookingpagetagmanager-analytics-tracking-id
generic

cve-2026-57858: cal.com declines to address stored xss in self-hosted version · ashton richards

https://ashtonr.com/blog/cve-2026-57858/
generic

GitHub - calcom/cal.diy: Scheduling infrastructure for absolutely everyone. · GitHub

https://github.com/calcom/cal.com

Vendor Advisories for CVE-2026-57858(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 26× in last 7d / 39× 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. 2026-08-20 22:55 UTCEPSS rescore
  2. 2026-08-20 21:02 UTCGHSA enrichment
  3. 2026-08-20 08:43 UTCGHSA enrichment
  4. 2026-08-19 20:26 UTCEG score recompute
  5. 2026-08-19 20:26 UTCGHSA enrichment
  6. 2026-08-19 17:04 UTCEPSS rescore
  7. 2026-08-19 08:08 UTCGHSA enrichment
  8. 2026-08-18 19:51 UTCEG score recompute
  9. 2026-08-18 19:51 UTCGHSA enrichment
  10. 2026-08-18 13:48 UTCEPSS rescore
  11. 2026-08-18 07:34 UTCGHSA enrichment
  12. 2026-08-17 19:14 UTCEG score recompute
  13. 2026-08-17 19:14 UTCGHSA enrichment
  14. 2026-08-17 13:47 UTCEPSS rescore
  15. 2026-08-17 06:33 UTCGHSA enrichment
  16. 2026-08-16 18:13 UTCEG score recompute
  17. 2026-08-16 18:13 UTCGHSA enrichment
  18. 2026-08-16 14:56 UTCEPSS rescore
  19. 2026-08-16 05:55 UTCEG score recompute
  20. 2026-08-16 05:55 UTCGHSA enrichment
  21. 2026-08-16 02:14 UTCEPSS rescore
  22. 2026-08-15 17:39 UTCGHSA enrichment
  23. 2026-08-15 05:22 UTCEG score recompute
  24. 2026-08-15 05:22 UTCGHSA enrichment
  25. 2026-08-15 01:30 UTCEPSS rescore
Show 14 more
  1. 2026-08-14 17:04 UTCGHSA enrichment
  2. 2026-08-14 04:47 UTCEG score recompute
  3. 2026-08-14 04:47 UTCGHSA enrichment
  4. 2026-08-13 22:00 UTCEPSS rescore
  5. 2026-08-13 16:30 UTCEG score recompute
  6. 2026-08-13 16:30 UTCGHSA enrichment
  7. 2026-08-13 16:17 UTCEG score recompute
  8. 2026-08-13 16:17 UTCGHSA enrichment
  9. 2026-08-13 14:11 UTCGHSA enrichment
  10. 2026-08-13 01:54 UTCEG score recompute
  11. 2026-08-13 01:54 UTCGHSA enrichment
  12. 2026-08-12 13:37 UTCEG score recompute
  13. 2026-08-12 12:35 UTCEG score recompute
  14. 2026-08-12 12:34 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-57858?
CVE-2026-57858 is a high vulnerability published on August 12, 2026. Cal.com Cal.diy versions 2.1.1 through 6.2.0 contain a stored cross-site scripting vulnerability in the BookingPageTagManager component that allows authenticated event owners to inject arbitrary JavaScript by supplying a malicious analytics tracking ID without sanitization. Attackers can close the…
When was CVE-2026-57858 disclosed?
CVE-2026-57858 was first published in the National Vulnerability Database on August 12, 2026, with the most recent update on August 13, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-57858 actively exploited?
CVE-2026-57858 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 65.1% of all scored CVEs.
What is the CVSS score of CVE-2026-57858?
CVE-2026-57858 has a CVSS v3 base score of 8.9 (NVD).
How do I remediate CVE-2026-57858?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-57858, 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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