Lucene search

K
ubuntucveUbuntu.comUB:CVE-2024-26883
HistoryApr 17, 2024 - 12:00 a.m.

CVE-2024-26883

2024-04-1700:00:00
ubuntu.com
ubuntu.com
9
linux kernel
bpf
stackmap vulnerability

7.8 High

CVSS3

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

7.8 High

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

5.1%

In the Linux kernel, the following vulnerability has been resolved: bpf:
Fix stackmap overflow check on 32-bit arches The stackmap code relies on
roundup_pow_of_two() to compute the number of hash buckets, and contains an
overflow check by checking if the resulting value is 0. However, on 32-bit
arches, the roundup code itself can overflow by doing a 32-bit left-shift
of an unsigned long value, which is undefined behaviour, so it is not
guaranteed to truncate neatly. This was triggered by syzbot on the
DEVMAP_HASH type, which contains the same check, copied from the hashtab
code. The commit in the fixes tag actually attempted to fix this, but the
fix did not account for the UB, so the fix only works on CPUs where an
overflow does result in a neat truncation to zero, which is not guaranteed.
Checking the value before rounding does not have this problem.

References

7.8 High

CVSS3

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

7.8 High

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

5.1%