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Fencer Intel
high 7.1

CVE-2026-63771 json

Adminer < 5.4.3 Cookie Injection via X-Forwarded-Prefix Header

published 3mo ago modified 18d ago also EUVD-2026-46070

cvss
7.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits
0
none known

Summary

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.

Patch / fix

  • vrana adminer 5.4.3
  • adminer Debian 14 5.4.3+dfsg-1

debian advisories DEBIAN-CVE-2026-63771

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3mo ago

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/vrana/adminer/issues/1298 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 6.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
CNA 3.1 7.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
CNA 4.0 6.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:L/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

  • vrana adminer

Classification

Weakness
  • CWE-113 Improper Neutralization of CRLF Sequences in HTTP Headers

References

Sources

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.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.