Debian Security Bug TrackerDEBIANCVE:CVE-2021-3491CVE-2021-3491
8.8 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
7.2 High
CVSS2
Access Vector
LOCAL
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:C/I:C/A:C
0.001 Low
EPSS
Percentile
20.2%
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).
| OS | Version | Architecture | Package | Version | Filename |
|---|---|---|---|---|---|
| Debian | 12 | all | linux | < 5.10.38-1 | linux_5.10.38-1_all.deb |
| Debian | 11 | all | linux | < 5.10.38-1 | linux_5.10.38-1_all.deb |
| Debian | 10 | all | linux | < 4.19.249-2 | linux_4.19.249-2_all.deb |
| Debian | 999 | all | linux | < 5.10.38-1 | linux_5.10.38-1_all.deb |
| Debian | 13 | all | linux | < 5.10.38-1 | linux_5.10.38-1_all.deb |
Related
8.8 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
7.2 High
CVSS2
Access Vector
LOCAL
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:C/I:C/A:C
0.001 Low
EPSS
Percentile
20.2%