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CVE-2021-36084

The CIL compiler in SELinux 3.2 has a use-after-free in __cil_verify_classperms (called from __cil_verify_classpermission and __cil_pre_verify_helper).

Published: Jul 1, 2021Updated: Nov 3, 2025 Sources: CVE List NVD BDU csafCWE-416
3.3LOW
NVD MITRE
EPSS Score
0.5%
Top 60.8%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available
Self-Check
OpenVAS

Description

Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the firmware version >= V3.1.0 and < V3.1.5 for the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP (incl. SIPLUS variant). These GNU/Linux vulnerabilities have been externally identified. Siemens has released new versions for the affected products and recommends to update to the latest versions. Note: This SSA advises vulnerabilities for firmware version V3.1 only; for versions < V3.1 refer to Siemens Security Bulletin SSB-439005 ( https://cert-portal.siemens.com/productcert/html/ssb-439005.html).

No summary for this CVE yet.

CVSS Vector Breakdown

AV:LAC:LPR:NUI:RS:UC:NI:NA:L
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:LAvailability
Low
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Weaknesses

CWE-416

Affected Products

SELinux project
oss-projectaka selinux, policycoreutils
SELinuxOn-prem
Operating Systems / linux-distro
fedoraproject
oss-project·USaka fedora project
fedoraOn-premOS
Operating Systems / linux-distro
and 2 more affected products View all →

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://nvd.nist.gov/vuln/detail/CVE-2021-36084&#13;
nvd.nist.gov
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31065
bugs.chromium.org
https://github.com/SELinuxProject/selinux/commit/f34d3d30c8325e4847a6b696fe7a3936a8a361f3
github.com
and 14 more references View all →

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