{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-93582", "assignerOrgId": "2e1bf29f-dc29-4ed8-830c-7b9348b6f0e8", "state": "PUBLISHED", "assignerShortName": "OTRS", "dateReserved": "2026-09-18T10:57:10.801Z", "datePublished": "2026-10-12T06:49:38.903Z", "dateUpdated": "2026-10-12T06:49:38.903Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "product": "OTRS", "vendor": "OTRS GmbH (former OTRS AG)", "versions": [{"status": "unaffected", "version": "7.0.x"}, {"status": "unaffected", "version": "8.0.x"}, {"status": "unaffected", "version": "2023.x"}, {"status": "unaffected", "version": "2024.x"}, {"status": "unaffected", "version": "2025.x"}, {"status": "unaffected", "version": "2026.x"}]}, {"defaultStatus": "affected", "product": "((OTRS)) Community Edition", "vendor": "OTRS GmbH (former OTRS AG)", "versions": [{"status": "affected", "version": "6.x"}]}], "credits": [{"lang": "en", "type": "finder", "value": "Special thanks to Mokrane ABDELMALEK (via Ghent University VDP programme) for finding this vulnerability"}], "datePublic": "2026-10-12T07:00:00.000Z", "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>The HTTP Basic Authentication modules in ((OTRS)) Community Edition 6 and prior accept the authenticated username from either the <code>REMOTE_USER</code> or <code>HTTP_REMOTE_USER</code> environment variable.&nbsp;In CGI and mod_perl based deployments, HTTP request headers may be mapped to corresponding <code>HTTP_*</code> environment variables. As a result, an unauthenticated remote attacker can supply a crafted <code>Remote-User</code> request header which is exposed to the application as <code>HTTP_REMOTE_USER</code>.&nbsp;When HTTP Basic Authentication is configured as the authentication backend, OTRS trusts this value as an already authenticated username and does not perform an additional password verification. An attacker may therefore authenticate through the Generic Interface as an existing agent or customer user without knowing the corresponding credentials.</p><p>The resulting privileges depend on the account being impersonated. Successful exploitation may allow access to confidential information and modification of data or configuration with the permissions of the affected user.&nbsp;Exploitation requires HTTP Basic Authentication to be configured as an authentication backend and a web server environment in which attacker-controlled HTTP headers are exposed through the corresponding <code>HTTP_*</code> environment variables.</p><p>OTRS 7 and later are not affected by this attack vector due to the&nbsp;use of Mojolicious/Hypnotoad and does not expose arbitrary request headers through <code>%ENV</code> in the manner required for exploitation. The supported <code>REMOTE_USER</code> mechanism additionally requires validation through the configured SSO shared secret. The unused <code>HTTP_REMOTE_USER</code> fallback has nevertheless been removed as a security-hardening measure.</p><p>Please note that ((OTRS)) Community Edition 6.x and before are vulnerable. Products based on the ((OTRS)) Community Edition also very likely to be affected<br></p>"}], "value": "The HTTP Basic Authentication modules in ((OTRS)) Community Edition 6 and prior accept the authenticated username from either the REMOTE_USER or HTTP_REMOTE_USER environment variable.\u00a0In CGI and mod_perl based deployments, HTTP request headers may be mapped to corresponding HTTP_* environment variables. As a result, an unauthenticated remote attacker can supply a crafted Remote-User request header which is exposed to the application as HTTP_REMOTE_USER.\u00a0When HTTP Basic Authentication is configured as the authentication backend, OTRS trusts this value as an already authenticated username and does not perform an additional password verification. An attacker may therefore authenticate through the Generic Interface as an existing agent or customer user without knowing the corresponding credentials.\n\nThe resulting privileges depend on the account being impersonated. Successful exploitation may allow access to confidential information and modification of data or configuration with the permissions of the affected user.\u00a0Exploitation requires HTTP Basic Authentication to be configured as an authentication backend and a web server environment in which attacker-controlled HTTP headers are exposed through the corresponding HTTP_* environment variables.\n\nOTRS 7 and later are not affected by this attack vector due to the\u00a0use of Mojolicious/Hypnotoad and does not expose arbitrary request headers through %ENV in the manner required for exploitation. The supported REMOTE_USER mechanism additionally requires validation through the configured SSO shared secret. The unused HTTP_REMOTE_USER fallback has nevertheless been removed as a security-hardening measure.\n\nPlease note that ((OTRS)) Community Edition 6.x and before are vulnerable. Products based on the ((OTRS)) Community Edition also very likely to be affected"}], "impacts": [{"capecId": "CAPEC-22", "descriptions": [{"lang": "en", "value": "CAPEC-22 Exploiting Trust in Client"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 9.4, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L", "version": "3.1"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-290", "description": "CWE-290 Authentication Bypass by Spoofing", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "2e1bf29f-dc29-4ed8-830c-7b9348b6f0e8", "shortName": "OTRS", "dateUpdated": "2026-10-12T06:49:38.903Z"}, "references": [{"url": "https://otrs.com/release-notes/otrs-security-advisory-2026-18/"}], "solutions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "Update to latest version of OTRS (2026.7.1. or later)."}], "value": "Update to latest version of OTRS (2026.7.1. or later)."}], "source": {"advisory": "OSA-2026-18", "defect": ["SecOPS#2026091710000411", "Issue#5466"], "discovery": "USER"}, "title": "Authentication Bypass via Spoofed Remote-User Header in HTTP Basic Authentication", "x_generator": {"engine": "Vulnogram 0.1.0-dev"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "OTRS", "vendor": "OTRS GmbH (former OTRS AG)", "versions": [{"status": "unaffected", "version": "7.0.x"}, {"status": "unaffected", "version": "8.0.x"}, {"status": "unaffected", "version": "2023.x"}, {"status": "unaffected", "version": "2024.x"}, {"status": "unaffected", "version": "2025.x"}, {"status": "unaffected", "version": "2026.x"}]}, {"defaultStatus": "affected", "product": "((OTRS)) Community Edition", "vendor": "OTRS GmbH (former OTRS AG)", "versions": [{"status": "affected", "version": "6.x"}]}], "source": "[email protected]"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "The HTTP Basic Authentication modules in ((OTRS)) Community Edition 6 and prior accept the authenticated username from either the REMOTE_USER or HTTP_REMOTE_USER environment variable.\u00a0In CGI and mod_perl based deployments, HTTP request headers may be mapped to corresponding HTTP_* environment variables. As a result, an unauthenticated remote attacker can supply a crafted Remote-User request header which is exposed to the application as HTTP_REMOTE_USER.\u00a0When HTTP Basic Authentication is configured as the authentication backend, OTRS trusts this value as an already authenticated username and does not perform an additional password verification. An attacker may therefore authenticate through the Generic Interface as an existing agent or customer user without knowing the corresponding credentials.\n\nThe resulting privileges depend on the account being impersonated. Successful exploitation may allow access to confidential information and modification of data or configuration with the permissions of the affected user.\u00a0Exploitation requires HTTP Basic Authentication to be configured as an authentication backend and a web server environment in which attacker-controlled HTTP headers are exposed through the corresponding HTTP_* environment variables.\n\nOTRS 7 and later are not affected by this attack vector due to the\u00a0use of Mojolicious/Hypnotoad and does not expose arbitrary request headers through %ENV in the manner required for exploitation. The supported REMOTE_USER mechanism additionally requires validation through the configured SSO shared secret. The unused HTTP_REMOTE_USER fallback has nevertheless been removed as a security-hardening measure.\n\nPlease note that ((OTRS)) Community Edition 6.x and before are vulnerable. Products based on the ((OTRS)) Community Edition also very likely to be affected"}], "id": "CVE-2026-93582", "lastModified": "2026-10-12T07:16:37.717", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 9.4, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.5, "source": "[email protected]", "type": "Secondary"}]}, "published": "2026-10-12T07:16:37.717", "references": [{"source": "[email protected]", "url": "https://otrs.com/release-notes/otrs-security-advisory-2026-18/"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-290"}], "source": "[email protected]", "type": "Secondary"}]}

{}

{}