Vulnerability Report

CVE-2021-3491

RCE

Title: Linux Linux Kernel RCE

RCE

Proof Of Concept

No public PoC currently indexed for CVE-2021-3491.

CWE Category CWE-787
Published Date Jun 04, 2021
Modified Date Nov 21, 2024
Exploit Status Not Found
Score 7.8 CVSS v3.1
Exploit Probability (EPSS)
0.63%

Vulnerability Summary

CVE-2021-3491: The io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS operation, which led to negative values being usedin mem_rw when reading /proc/<PID>/mem. This could be used to create a heap overflow leading to arbitrary code execution in the kernel. It was addressed via commit d1f82808877b ("io_uring: truncate lengths larger than MAX_RW_COUNT on provide buffers") (v5.13-rc1) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced in ddf0322db79c ("io_uring: add IORING_OP_PROVIDE_BUFFERS") (v5.7-rc1).

Impacted Vendors

L
linux 1
U
ubuntu 2
C
canonical 1

Reference Links

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d1f82808877bb10d3deee7cf3374a4eb3fb582db https://security.netapp.com/advisory/ntap-20210716-0004/ https://ubuntu.com/security/notices/USN-4949-1 https://ubuntu.com/security/notices/USN-4950-1 https://www.openwall.com/lists/oss-security/2021/05/11/13 https://www.zerodayinitiative.com/advisories/ZDI-21-589/ https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d1f82808877bb10d3deee7cf3374a4eb3fb582db https://security.netapp.com/advisory/ntap-20210716-0004/ https://ubuntu.com/security/notices/USN-4949-1 https://ubuntu.com/security/notices/USN-4950-1 https://www.openwall.com/lists/oss-security/2021/05/11/13 https://www.zerodayinitiative.com/advisories/ZDI-21-589/
CVSS v3.1
Source Entity [email protected]
Severity HIGH
7.8
Attack Vector
LOCAL
Complexity
HIGH
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
CHANGED
RAW VECTOR CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v3.1
Source Entity [email protected]
Severity HIGH
8.8
Attack Vector
LOCAL
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
CHANGED
RAW VECTOR CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v2.0
Source Entity [email protected]
Severity HIGH
7.2
Access Vector
N/A
Authentication
N/A
RAW VECTOR AV:L/AC:L/Au:N/C:C/I:C/A:C

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2021-3491 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data or affected products updated.

PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector LOCAL
Complexity HIGH
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected Stack

No specific products linked.