CVE-2026-63771

HIGHPre-NVD 7.17.1—
EchelonGraph scoreHIGH confidence

Score 7.1 from GitHub Security Advisory published 2026-07-20. the CNA's CVSS baseline 7.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:vulncheck, epss, ghsa
Trending — 4 sources updated this weekElevated
7.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.1Exploit: NoneExposed: 0

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

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.

CVSS v3
7.1
EG Score
7.1(high)
EG Risk
48(Track)
EG Risk 48/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity71% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
15.6%
KEV
Not listed

Published

July 20, 2026

Last Modified

July 21, 2026

Advisory Details (4)

Auto-updated Jul 20, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

Adminer < 5.4.3 Cookie Injection via X-Forwarded-Prefix Header | Advisories | VulnCheck

https://www.vulncheck.com/advisories/adminer-cookie-injection-via-x-forwarded-prefix-header
github Patch Available🟡 PoC Available

Cookie Attribute Injection via Unsanitized X-Forwarded-Prefix in Set-Cookie Headers · Advisory · vrana/adminer · GitHub

https://github.com/vrana/adminer/security/advisories/GHSA-c533-9qwm-8w5h
generic

Releases · vrana/adminer · GitHub

https://github.com/vrana/adminer/releases#release-v5.4.3
generic

Cookie Header Injection via Unsanitized X-Forwarded-Prefix in Set-Cookie Path · Issue #1298 · vrana/adminer · GitHub

https://github.com/vrana/adminer/issues/1298

Vendor Advisories for CVE-2026-63771(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 14× in last 7d / 14× 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. 2026-07-23 03:22 UTCEG score recompute
  2. 2026-07-22 23:30 UTCEG score recompute
  3. 2026-07-22 23:30 UTCGHSA enrichment
  4. 2026-07-22 14:08 UTCEPSS rescore
  5. 2026-07-22 14:08 UTCEPSS rescore
  6. 2026-07-21 15:25 UTCEPSS rescore
  7. 2026-07-21 15:25 UTCEPSS rescore
  8. 2026-07-20 22:43 UTCEG score recompute
  9. 2026-07-20 22:42 UTCGHSA enrichment
  10. 2026-07-20 21:48 UTCEG score recompute
  11. 2026-07-20 21:48 UTCGHSA enrichment
  12. 2026-07-20 20:42 UTCEG score recompute
  13. 2026-07-20 19:13 UTCEG score recompute
  14. 2026-07-20 19:12 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-63771?
CVE-2026-63771 is a high vulnerability published on July 20, 2026. 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…
When was CVE-2026-63771 disclosed?
CVE-2026-63771 was first published in the National Vulnerability Database on July 20, 2026, with the most recent update on July 21, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-63771 actively exploited?
CVE-2026-63771 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 15.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-63771?
CVE-2026-63771 has a CVSS v4.0 base score of 7.1 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-63771?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-63771, 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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