Vulnerability Report

CVE-2021-3490

Title: Linux Linux Kernel Memory Corruption

Memory Corruption

Proof Of Concept

PoC Available for CVE-2021-3490

CWE Category CWE-125
Published Date Jun 04, 2021
Modified Date Nov 21, 2024
Exploit Status Available
Score 7.8 CVSS v3.1
Exploit Probability (EPSS)
27.48%

Vulnerability Summary

CVE-2021-3490: The eBPF ALU32 bounds tracking for bitwise ops (AND, OR and XOR) in the Linux kernel did not properly update 32-bit bounds, which could be turned into out of bounds reads and writes in the Linux kernel and therefore, arbitrary code execution. This issue was fixed via commit 049c4e13714e ("bpf: Fix alu32 const subreg bound tracking on bitwise operations") (v5.13-rc4) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. The AND/OR issues were introduced by commit 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking") (5.7-rc1) and the XOR variant was introduced by 2921c90d4718 ("bpf:Fix a verifier failure with xor") ( 5.10-rc1).

Impacted Vendors

L
linux 1
U
ubuntu 2
C
canonical 1

Reference Links

http://packetstormsecurity.com/files/164015/Linux-eBPF-ALU32-32-bit-Invalid-Bounds-Tracking-Local-Privilege-Escalation.html https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=049c4e13714ecbca567b4d5f6d563f05d431c80e 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/2021/05/11/11 https://www.zerodayinitiative.com/advisories/ZDI-21-606/ http://packetstormsecurity.com/files/164015/Linux-eBPF-ALU32-32-bit-Invalid-Bounds-Tracking-Local-Privilege-Escalation.html https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=049c4e13714ecbca567b4d5f6d563f05d431c80e 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/2021/05/11/11 https://www.zerodayinitiative.com/advisories/ZDI-21-606/
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
7.8
Attack Vector
LOCAL
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/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-2021-3490 Exploits & PoCs (Proof Of Concept)

GitHub https://github.com/chompie1337/Linux_LPE_eBPF_CVE-2021-3490
View Code
GitHub https://github.com/pivik271/CVE-2021-3490
View Code
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.