CVE-2026-53963

CRITICALNVD 9.09.0—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.0 under NVD CVSS v3. EPSS exploit probability: 0.5%, top 64% 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
Trending — 4 sources updated this week
9.0
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 9.0Exploit: NoneExposed: 0

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

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, a malicious second factor name on an attacker-controlled account was not escaped in the delete confirmation dialog, allowing stored cross-site scripting when an administrator impersonated that account. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

CVSS v3
9.0
EG Score
9.0(medium)
EPSS
36.4%
KEV
Not listed

Published

July 9, 2026

Last Modified

July 14, 2026

Advisory Details (5)

Auto-updated Jul 9, 2026
Patch available. Sources: github_commit, github.
github Patch Available

Stored-XSS in 2FA delete confirmation modal · Advisory · discourse/discourse · GitHub

https://github.com/discourse/discourse/security/advisories/GHSA-wg5x-7f23-m3r5
github_commit

commit daea5214d833 (discourse/discourse)

Fix landed in discourse/discourse commit daea5214d833 — awaiting tagged release

https://github.com/discourse/discourse/commit/daea5214d833eacbdd3b1a78d99eb14e9cabd915
github_commit

commit d92973e51a46 (discourse/discourse)

Fix landed in discourse/discourse commit d92973e51a46 — awaiting tagged release

https://github.com/discourse/discourse/commit/d92973e51a46cf6dd20c71e6068e6769b67eea5b
github_commit

commit 529e17d4d570 (discourse/discourse)

Fix landed in discourse/discourse commit 529e17d4d570 — awaiting tagged release

https://github.com/discourse/discourse/commit/529e17d4d570a48972e7cf64720e5dd1fdf23ca8
github_commit

commit 40de62cddadc (discourse/discourse)

Fix landed in discourse/discourse commit 40de62cddadc — awaiting tagged release

https://github.com/discourse/discourse/commit/40de62cddadc65c328a1028ab999f3fa94adbfed

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 31× in last 7d / 31× 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 01:17 UTCEG score recompute
  2. 2026-07-15 21:02 UTCEG score recompute
  3. 2026-07-15 16:57 UTCEPSS rescore
  4. 2026-07-15 16:57 UTCEPSS rescore
  5. 2026-07-15 16:47 UTCEG score recompute
  6. 2026-07-15 12:30 UTCEG score recompute
  7. 2026-07-15 08:14 UTCEG score recompute
  8. 2026-07-15 04:00 UTCEG score recompute
  9. 2026-07-15 02:00 UTCEPSS rescore
  10. 2026-07-15 02:00 UTCEPSS rescore
  11. 2026-07-14 23:45 UTCEG score recompute
  12. 2026-07-14 19:31 UTCEG score recompute
  13. 2026-07-14 15:17 UTCEG score recompute
  14. 2026-07-14 11:02 UTCEG score recompute▲ 1.70
  15. 2026-07-14 01:43 UTCNVD updateCVSS v3 → 9 · severity → CRITICAL
  16. 2026-07-13 22:51 UTCEG score recompute
  17. 2026-07-13 22:31 UTCEPSS rescore
  18. 2026-07-13 10:47 UTCEG score recompute
  19. 2026-07-13 06:13 UTCEPSS rescore
  20. 2026-07-13 06:13 UTCEPSS rescore
  21. 2026-07-12 22:43 UTCEG score recompute
  22. 2026-07-12 10:39 UTCEG score recompute
  23. 2026-07-12 05:46 UTCEPSS rescore
  24. 2026-07-11 22:34 UTCEG score recompute
  25. 2026-07-11 10:30 UTCEG score recompute
Show 6 more
  1. 2026-07-11 08:27 UTCEPSS rescore
  2. 2026-07-11 08:27 UTCEPSS rescore
  3. 2026-07-10 22:26 UTCEG score recompute
  4. 2026-07-10 10:15 UTCEG score recompute
  5. 2026-07-09 22:10 UTCEG score recompute
  6. 2026-07-09 22:10 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-53963?
CVE-2026-53963 is a critical vulnerability published on July 9, 2026. Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, a malicious second factor name on an attacker-controlled account was not escaped in the delete confirmation dialog, allowing stored cross-site scripting when an administrator impersonated that…
When was CVE-2026-53963 disclosed?
CVE-2026-53963 was first published in the National Vulnerability Database on July 9, 2026, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53963 actively exploited?
CVE-2026-53963 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 36.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-53963?
CVE-2026-53963 has a CVSS v3 base score of 9.0 (NVD).
How do I remediate CVE-2026-53963?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53963, 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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