CVE-2026-8106

A reflected HTML injection vulnerability was identified in the GitHub Enterprise Server Management Console login page that could allow credential theft. The redirect_to query parameter on the /setup/unlock endpoint was reflected into an HTML attribute without proper sanitization, enabling an attacker to inject a form element that could capture administrator credentials. Exploitation required an administrator to click a crafted link and enter their credentials. This vulnerability affected GitHub Enterprise Server versions 3.19.1 through 3.19.5 and 3.20.0 through 3.20.1, and was fixed in versions 3.19.6 and 3.20.2. This vulnerability was reported via the GitHub Bug Bounty program.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.6	Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.2	Release Notes Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:github:enterprise_server::::::::
	cpe:2.3:a:github:enterprise_server::::::::

History

11 May 2026, 17:12

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.1
First Time		Github Github enterprise Server
CPE		cpe:2.3:a:github:enterprise_server::::::::
References	~~() https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.6 -~~	() https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.6 - Release Notes, Vendor Advisory
References	~~() https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.2 -~~	() https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.2 - Release Notes, Vendor Advisory

07 May 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-07 22:16

Updated : 2026-05-11 17:12

NVD link : CVE-2026-8106

Mitre link : CVE-2026-8106

CVE.ORG link : CVE-2026-8106

JSON object : View

Products Affected

github

enterprise_server

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

{"id": "CVE-2026-8106", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 6.1, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.7, "exploitabilityScore": 2.8}], "cvssMetricV40": [{"type": "Secondary", "source": "product-cna@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 5.9, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "ACTIVE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "published": "2026-05-07T22:16:37.377", "references": [{"url": "https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.6", "tags": ["Release Notes", "Vendor Advisory"], "source": "product-cna@github.com"}, {"url": "https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.2", "tags": ["Release Notes", "Vendor Advisory"], "source": "product-cna@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "product-cna@github.com", "description": [{"lang": "en", "value": "CWE-79"}]}], "descriptions": [{"lang": "en", "value": "A reflected HTML injection vulnerability was identified in the GitHub Enterprise Server Management Console login page that could allow credential theft. The redirect_to query parameter on the /setup/unlock endpoint was reflected into an HTML attribute without proper sanitization, enabling an attacker to inject a form element that could capture administrator credentials. Exploitation required an administrator to click a crafted link and enter their credentials. This vulnerability affected GitHub Enterprise Server versions 3.19.1 through 3.19.5 and 3.20.0 through 3.20.1, and was fixed in versions 3.19.6 and 3.20.2. This vulnerability was reported via the GitHub Bug Bounty program."}], "lastModified": "2026-05-11T17:12:47.430", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F71305E0-C008-45FF-8EDC-46D14F07DD51", "versionEndExcluding": "3.19.6", "versionStartIncluding": "3.19.1"}, {"criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FC8A09E8-5FFE-43F1-BC1A-14A298264D80", "versionEndExcluding": "3.20.2", "versionStartIncluding": "3.20.0"}], "operator": "OR"}]}], "sourceIdentifier": "product-cna@github.com"}