What’s Vulnerable › Vulnerabilities

CVE-2026-63771: Adminer < 5.4.3 Cookie Injection via X-Forwarded-Prefix Header

• Severity: high (CVSS 7.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-20 · updated 2026-10-24
• Weakness: CWE-113

Description

Adminer before 5.4.3 contains a cookie injection vulnerability that allows attackers to manipulate cookie attributes by injecting arbitrary values through the unsanitized X-Forwarded-Prefix HTTP header used in Set-Cookie path attributes. Attackers can exploit a misconfigured reverse proxy to downgrade SameSite protection and enable cross-origin authenticated requests, bypassing cookie security controls.

Affected products

• vrana adminer: before 5.4.3 — fixed in 5.4.3

How to fix

Upgrade to a fixed version: vrana adminer 5.4.3. Check the vendor advisory for mitigations.

References

• https://github.com/vrana/adminer/issues/1298
• https://github.com/vrana/adminer/releases#release-v5.4.3
• https://github.com/vrana/adminer/security/advisories/GHSA-c533-9qwm-8w5h
• https://www.vulncheck.com/advisories/adminer-cookie-injection-via-x-forwarded-prefix-header

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