CVE-2026-63771
Adminer < 5.4.3 Cookie Injection via X-Forwarded-Prefix Header
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Adminer < 5.4.3 Cookie Injection via X-Forwarded-Prefix Header
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.
- Record
CVE-2026-63771- CVSS 4.0
- 6.0 Medium
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 - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N - Weakness
- CWE-113
- Updated
- 2026-11-02
EUVDEUVD-2026-46070
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.
- Record
EUVD-2026-46070- CVSS 4.0
- 6.0 Medium
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-hvv2-8jpj-gr8h
Adminer before 5.4.3 contains a cookie injection vulnerability that allows attackers to...
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.
- Record
GHSA-hvv2-8jpj-gr8h- CVSS 4.0
- 6.0 Medium
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 - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N - Weakness
- CWE-113
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-63771- CVSS 4.0
- 6.0 Medium
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 - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N - Weakness
- CWE-113
- Updated
- 2026-11-02
OSV
Adminer < 5.4.3 Cookie Injection via X-Forwarded-Prefix Header
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.
- Record
CVE-2026-63771- CVSS 4.0
- 6.0 Medium
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 - Weakness
- CWE-113
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-63771
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.
- Record
DEBIAN-CVE-2026-63771- CVSS 4.0
- 6.0 Medium
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 - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-63771
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.
- Record
UBUNTU-CVE-2026-63771- CVSS 4.0
- 6.0 Medium
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 - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
adminerDebian:12 |
All versions, plus listed versions 4.8.1-14.8.1-24.8.1-45.1.0-15.2.1+dfsg-1 Show 12 moreShow less5.3.0+dfsg-15.4.0+dfsg-15.4.1+dfsg-15.4.2+dfsg-15.4.3+dfsg-15.4.4+dfsg-16.0.0-16.0.1-16.0.2-16.1.0-16.1.1-16.1.2-1 |
None known |
adminerDebian:13 |
All versions, plus listed versions 5.2.1+dfsg-15.3.0+dfsg-15.4.0+dfsg-15.4.1+dfsg-15.4.2+dfsg-1 Show 8 moreShow less5.4.3+dfsg-15.4.4+dfsg-16.0.0-16.0.1-16.0.2-16.1.0-16.1.1-16.1.2-1 |
None known |
adminerDebian:14 |
before 5.4.3+dfsg-1, plus listed versions 5.2.1+dfsg-15.3.0+dfsg-15.4.0+dfsg-15.4.1+dfsg-15.4.2+dfsg-1 |
5.4.3+dfsg-1 |
adminerUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 4.2.1-14.2.1-1ubuntu14.2.1-1ubuntu1+esm1 |
None known |
adminerUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 4.3.1-24.5.0-14.6.1-14.6.2-14.6.2-1ubuntu0.1~esm1 |
None known |
adminerUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 4.7.2-14.7.4-14.7.5-14.7.6-14.7.6-1ubuntu0.1~esm1 |
None known |
adminerUbuntu:22.04:LTS |
All versions, plus listed versions 4.7.9-24.8.1-1 |
None known |
adminerUbuntu:24.04:LTS |
All versions, plus listed versions 4.8.1-14.8.1-1ubuntu14.8.1-2 |
None known |
adminerUbuntu:26.10 |
All versions, plus listed versions 5.4.1+dfsg-15.4.2+dfsg-15.4.4+dfsg-16.0.0-1 |
None known |
adminerUbuntu:26.04:LTS |
All versions, plus listed versions 5.2.1+dfsg-15.3.0+dfsg-15.4.0+dfsg-15.4.1+dfsg-1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-63771 is a medium vulnerability (CVSS 6.0) in Vrana Adminer, published July 20, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.43%, the 37th percentile. Fixed in adminer 5.4.3+dfsg-1.