3.3
LOW
CVE-2021-36087
SELinux CIL Buffer Over-read Vulnerability
Description

The CIL compiler in SELinux 3.2 has a heap-based buffer over-read in ebitmap_match_any (called indirectly from cil_check_neverallow). This occurs because there is sometimes a lack of checks for invalid statements in an optional block.

INFO

Published Date :

July 1, 2021, 3:15 a.m.

Last Modified :

Nov. 7, 2023, 3:36 a.m.

Source :

[email protected]

Remotely Exploitable :

No

Impact Score :

1.4

Exploitability Score :

1.8
Public PoC/Exploit Available at Github

CVE-2021-36087 has a 8 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

Affected Products

The following products are affected by CVE-2021-36087 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Fedoraproject fedora
1 Selinux_project selinux
: Total Affected Vendor : 2 | Products : 2
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-36087.

URL Resource
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32675 Exploit Issue Tracking Patch Third Party Advisory
https://github.com/SELinuxProject/selinux/commit/340f0eb7f3673e8aacaf0a96cbfcd4d12a405521 Patch Third Party Advisory
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-585.yaml Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/
https://lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ%40mail.gmail.com/T/

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Profile Photo
Srinu-rj/spring-food-app

None

Dockerfile Roff Java

Updated: 1 month, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : Oct. 7, 2024, 8:52 a.m. This repo has been linked 127 different CVEs too.
Profile Photo
mmbazm/secure_license_server

None

Dockerfile Python

Updated: 1 week, 1 day ago
0 stars 0 fork 0 watcher
Born at : Oct. 5, 2024, 4:56 p.m. This repo has been linked 68 different CVEs too.
Profile Photo
fokypoky/places-list

None

asp-net-core csharp docker dockerfile javascript react webapi docker-compose

C# Dockerfile HTML JavaScript CSS

Updated: 7 months, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : Feb. 22, 2024, 6:42 p.m. This repo has been linked 383 different CVEs too.
Profile Photo
cdupuis/image-api

None

TypeScript

Updated: 1 year, 11 months ago
0 stars 0 fork 0 watcher
Born at : Dec. 6, 2022, 12:43 p.m. This repo has been linked 43 different CVEs too.
Profile Photo
vincent-deng/veracode-container-security-finding-parser

Map Vulnerabilities into Different Layers of the Container Image

Python

Updated: 1 year, 10 months ago
1 stars 0 fork 0 watcher
Born at : Oct. 5, 2022, 12:07 p.m. This repo has been linked 1276 different CVEs too.
Profile Photo
yeforriak/snyk-to-cve

None

Go

Updated: 2 years, 7 months ago
0 stars 0 fork 0 watcher
Born at : March 29, 2022, 1:06 p.m. This repo has been linked 13 different CVEs too.
Profile Photo
akiraabe/myapp-container-jaxrs

None

Java Shell

Updated: 2 years, 8 months ago
0 stars 0 fork 0 watcher
Born at : March 8, 2022, 11:16 a.m. This repo has been linked 25 different CVEs too.
Profile Photo
kenlavbah/log4jnotes

None

Updated: 2 years, 11 months ago
0 stars 0 fork 0 watcher
Born at : Dec. 16, 2021, 8:16 p.m. This repo has been linked 24 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-36087 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-36087 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Added Reference MITRE https://lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ%40mail.gmail.com/T/ [No types assigned]
    Added Reference MITRE https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/ [No types assigned]
    Removed Reference MITRE https://lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ@mail.gmail.com/T/
    Removed Reference MITRE https://lists.fedoraproject.org/archives/list/[email protected]/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/
  • Modified Analysis by [email protected]

    Nov. 17, 2021

    Action Type Old Value New Value
    Changed Reference Type https://github.com/SELinuxProject/selinux/commit/340f0eb7f3673e8aacaf0a96cbfcd4d12a405521 No Types Assigned https://github.com/SELinuxProject/selinux/commit/340f0eb7f3673e8aacaf0a96cbfcd4d12a405521 Patch, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/ Mailing List, Third Party Advisory
    Changed Reference Type https://lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ@mail.gmail.com/T/ No Types Assigned https://lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ@mail.gmail.com/T/ Mailing List, Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Nov. 15, 2021

    Action Type Old Value New Value
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/ [No Types Assigned]
  • CVE Modified by [email protected]

    Jul. 26, 2021

    Action Type Old Value New Value
    Changed Description The CIL compiler in SELinux 3.2 has a heap-based buffer over-read in ebitmap_match_any (called indirectly from cil_check_neverallow). NOTE: bad0a746e9f4cf260dedba5828d9645d50176aac is cited in the OSV "fixed" field but does not have a code change. The CIL compiler in SELinux 3.2 has a heap-based buffer over-read in ebitmap_match_any (called indirectly from cil_check_neverallow). This occurs because there is sometimes a lack of checks for invalid statements in an optional block.
    Removed Reference https://github.com/SELinuxProject/selinux/commit/bad0a746e9f4cf260dedba5828d9645d50176aac [Patch, Third Party Advisory]
    Added Reference https://lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ@mail.gmail.com/T/ [No Types Assigned]
    Added Reference https://github.com/SELinuxProject/selinux/commit/340f0eb7f3673e8aacaf0a96cbfcd4d12a405521 [No Types Assigned]
  • Reanalysis by [email protected]

    Jul. 26, 2021

    Action Type Old Value New Value
    Removed CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
  • Initial Analysis by [email protected]

    Jul. 07, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:L/AC:L/Au:N/C:N/I:N/A:P)
    Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Changed Reference Type https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32675 No Types Assigned https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32675 Exploit, Issue Tracking, Patch, Third Party Advisory
    Changed Reference Type https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-585.yaml No Types Assigned https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-585.yaml Third Party Advisory
    Changed Reference Type https://github.com/SELinuxProject/selinux/commit/bad0a746e9f4cf260dedba5828d9645d50176aac No Types Assigned https://github.com/SELinuxProject/selinux/commit/bad0a746e9f4cf260dedba5828d9645d50176aac Patch, Third Party Advisory
    Added CWE NIST CWE-125
    Added CPE Configuration OR *cpe:2.3:o:selinux_project:selinux:3.2:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-36087 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-36087 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.07 }} 0.02%

score

0.29464

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
: