CVE-2026-53518

HIGHPre-NVD 7.68.1
EchelonGraph scoreLOW confidence

This high-severity CVE scores 8.1 under the CNA's CVSS (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). 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: cna:github_m
7.6
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: —CVSS: 7.6Exploit: NoneExposed: 0

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

Better Auth is an authentication and authorization library for TypeScript. From 1.6.0 until 1.6.11, the @better-auth/oauth-provider POST /oauth2/token endpoint for the authorization_code grant redeems a single-use authorization code through a non-atomic find-then-delete sequence, allowing two concurrent requests to pass the read step and mint independent access tokens, refresh tokens, and ID tokens; legacy /oauth2/token and /mcp/token paths in oidc-provider and mcp plugins share the same primitive. This issue is fixed in version 1.6.11.

CVSS v3
7.6
EG Score
8.1(low)
EPSS
—
KEV
Not listed

Published

July 7, 2026

Last Modified

July 15, 2026

Advisory Details (3)

Auto-updated Jul 15, 2026
Patch available. Sources: github, github_commit, github_release.
github Patch Available

@better-auth/oauth-provider: OAuth authorization-code grant allows concurrent redemption when two token requests race the find-then-delete primitive · Advisory · better-auth/better-auth · GitHub

https://github.com/better-auth/better-auth/security/advisories/GHSA-7w99-5wm4-3g79
github_release Patch Available

v1.6.11

Patch available: better-auth/better-auth v1.6.11

https://github.com/better-auth/better-auth/releases/tag/v1.6.11
github_commit

commit b4bc65a00778 (better-auth/better-auth)

Fix landed in better-auth/better-auth commit b4bc65a00778 — awaiting tagged release

https://github.com/better-auth/better-auth/commit/b4bc65a007784b2eb0efb459e5fa6fd8055d3ec9

Vendor Advisories for CVE-2026-53518(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 16× in last 7d / 19× 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. 2026-07-15 17:28 UTCMITRE cvelistV5CVSS v3 → 7.6 · CVSS v4 → 7.6
  2. 2026-07-15 15:44 UTCEG score recompute
  3. 2026-07-15 04:46 UTCEG score recompute
  4. 2026-07-14 17:35 UTCEG score recompute
  5. 2026-07-14 06:38 UTCEG score recompute
  6. 2026-07-13 19:39 UTCEG score recompute
  7. 2026-07-13 08:42 UTCEG score recompute
  8. 2026-07-12 21:45 UTCEG score recompute
  9. 2026-07-12 10:48 UTCEG score recompute
  10. 2026-07-11 23:50 UTCEG score recompute
  11. 2026-07-11 12:53 UTCEG score recompute
  12. 2026-07-11 01:56 UTCEG score recompute
  13. 2026-07-10 14:59 UTCEG score recompute
  14. 2026-07-10 04:02 UTCEG score recompute
  15. 2026-07-09 17:03 UTCEG score recompute
  16. 2026-07-09 06:05 UTCEG score recompute
  17. 2026-07-08 19:07 UTCEG score recompute
  18. 2026-07-08 08:10 UTCEG score recompute
  19. 2026-07-07 21:13 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(4)

What is CVE-2026-53518?
CVE-2026-53518 is a high vulnerability published on July 7, 2026. Better Auth is an authentication and authorization library for TypeScript. From 1.6.0 until 1.6.11, the @better-auth/oauth-provider POST /oauth2/token endpoint for the authorization_code grant redeems a single-use authorization code through a non-atomic find-then-delete sequence, allowing two…
When was CVE-2026-53518 disclosed?
CVE-2026-53518 was first published in the National Vulnerability Database on July 7, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-53518?
CVE-2026-53518 has a CVSS v3 base score of 7.6 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 8.1. The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-53518?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53518, 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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