What is CVE-2026-63756?

CVE-2026-63756 is a high-severity vulnerability in Surrealdb, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.1/10. Published 2026-07-20.

How severe is CVE-2026-63756?

High severity. CVSS v3 base score is 8.1 out of 10.

Vulnerability in Surrealdb

CVE-2026-63756

SurrealDB versions before 3.1.0 contain a time-of-check/time-of-use race condition in the HTTP /rpc endpoint that allows unauthenticated requests to inherit authenticated session state. Unauthenticated attackers can send concurrent requests to the /rpc endpoint while legitimate authenticated traffic is active to execute operations with hijacked user privileges.

Vulnerability class: Race Condition

EPSS: 0.004 (29.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Surrealdb — versions 0, 3.1.0

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)

References

disclosure@vulncheck.com (vendor-advisory, Vendor Advisory)
disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2026-63756?: CVE-2026-63756 is a high-severity vulnerability in Surrealdb, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.1/10. Published 2026-07-20.
How severe is CVE-2026-63756?: High severity. CVSS v3 base score is 8.1 out of 10.