CVE-2026-62386 json
Grav < 1.0.0-rc.16 Authentication Bypass via token URL Parameter
published 3mo ago modified 18d ago also EUVD-2026-45086
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 26%
- public exploits
- 0
- none known
Summary
The Grav API plugin (getgrav/grav-plugin-api) before 1.0.0-rc.16 accepts JWT access tokens through the ?token= URL query parameter on every API route (JwtAuthenticator::extractBearerToken fallback). Because tokens are embedded in URLs, they are logged verbatim in web server access logs, leaked via the Referer header, stored in browser history, and captured by upstream proxy and CDN logs, exposing valid admin access tokens. A leaked token grants unauthorized API access, including reading configuration and user data, creating admin accounts, modifying system settings, and deleting pages.
Patch / fix
- getgrav grav 1.0.0-rc.16
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 3mo ago
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- github.com https://github.com/getgrav/grav/security/advisories/GHSA-4hpj-wmpw-ghwq referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CNA | 4.0 | 8.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- getgrav grav
Classification
- Weakness
-
- CWE-598 Use of HTTP Request With Sensitive Query String
References
-
github.com
/getgrav/grav/security/advisories/GHSA-4hpj-wmpw-ghwq
vendor-advisory, exploit
-
vulncheck.com
/advisories/grav-rc-16-authentication-bypass-via-token-url-parameter
third-party-advisory
Sources
- CVE List CVE-2026-62386
- NVD CVE-2026-62386
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.