CVE-2026-63761 | SurrealDB before 3.1.0 silently substitutes the ES384 algori… | CVSS 4.3 MEDIUM

Description

SurrealDB before 3.1.0 silently substitutes the ES384 algorithm when a JWT access method is configured with ALGORITHM ES512 (DEFINE ACCESS ... TYPE JWT ALGORITHM ES512), because the underlying jsonwebtoken crate (v10.x) has no ES512 variant and the mapping defaults to ES384 without any error, warning, or log message. Users who supply the correct P-521 key for ES512 experience authentication handshake failures due to the curve mismatch with ES384 (which expects P-384), and tokens are rejected by external systems expecting genuine ES512 signatures. The flaw cannot be used to forge tokens or compromise data confidentiality or integrity, as ES384 remains cryptographically strong.

Metadata

CVE ID: CVE-2026-63761
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-07-18 12:30 UTC
Published: 2026-07-20 12:04 UTC
Last updated: 2026-07-20 13:48 UTC
Primary CWE: CWE-327
Use of a Broken or Risky Cryptographic Algorithm
Vendor / Product: surrealdb / surrealdb
Sources: cve.org · NVD

Severity & Metrics

4.3 MEDIUM CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
surrealdb	surrealdb	—	0 < 3.1.0, 3.1.0

Weakness (CWE)

CWE	Source	Description
CWE-327	cna	Use of a Broken or Risky Cryptographic Algorithm

CVSS scores (2)

Score	Severity	Version	Source	Vector
5.3	MEDIUM	4.0	cna	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
4.3	MEDIUM	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

References (2)

GitHub Security Advisory (GHSA-fwg2-gr34-q3w8) https://github.com/surrealdb/surrealdb/security/advisories/GHSA-fwg2-gr34-q3w8
VulnCheck Advisory: SurrealDB before 3.1.0 Algorithm Downgrade via ES512 https://www.vulncheck.com/advisories/surrealdb-before-algorithm-downgrade-via-es512