grsecurity Role-Based Access Control (RBAC) security bypass
| grsecurity-rbac-security-bypass (41952) |  Low Risk |
Description:
grsecurity could allow a local attacker to bypass security restrictions, caused by an error in the user_transition_deny and user_transition_allow Role-Based Access Control (RBAC) system rules. An attacker could exploit this vulnerability via calls to sys_setfsuid() and sys_setfsgid() to bypass RBAC system rules.
*CVSS:
| Base Score: | 3.6 |
| Access Vector: | Local |
| Access Complexity: | Low |
| Authentication: | None |
| Confidentiality Impact: | Partial |
| Integrity Impact: | Partial |
| Availability Impact: | None |
| Temporal Score: | 2.7 |
| Exploitability: | Unproven |
| Remediation Level: | Official-Fix |
| Report Confidence: | Confirmed |
Consequences:
Bypass Security
Remedy:
Upgrade to the latest version of grsecurity (2.1.11-2.6.24.5 or 2.1.11-2.4.36.2 or later), available from the grsecurity Download Web site. See References.
References:
- grsecurity Download Web site: grsecurity-2.1.11-2.4.36.2-200804211830.patch.gz.
- grsecurity News Web site: [04/21] grsecurity 2.1.11 patches updated, 2.6.24.5 supported.
- BID-28889: grsecurity Multiple RBAC Local Security Bypass Vulnerabilities
- CVE-2008-1940: The RBAC functionality in grsecurity before 2.1.11-2.6.24.5 and 2.1.11-2.4.36.2 does not enforce user_transition_deny and user_transition_allow rules for the (1) sys_setfsuid and (2) sys_setfsgid calls, which allows local users to bypass restrictions for those calls.
- SA29899: grsecurity RBAC User Transition Security Issue
- SECTRACK ID: 1019919: grsecurity Lets Local Users Bypass Role Based Access Control Rules
- VUPEN/ADV-2008-1323: grsecurity RBAC User Transition Rules Local Security Bypass Issue
Platforms Affected:
- grsecurity grsecurity
Reported:
Apr 21, 2008
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* According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES "AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.
The information within this database may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. In no event shall IBM be held liable for any damages whatsoever arising out of or in connection with the use or spread of this information.