CVE-2021-3864
7 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
6.9 Medium
AI Score
Confidence
High
0.0004 Low
EPSS
Percentile
5.1%
A flaw was found in the way the dumpable flag setting was handled when certain SUID binaries executed its descendants. The prerequisite is a SUID binary that sets real UID equal to effective UID, and real GID equal to effective GID. The descendant will then have a dumpable value set to 1. As a result, if the descendant process crashes and core_pattern is set to a relative value, its core dump is stored in the current directory with uid:gid permissions. An unprivileged local user with eligible root SUID binary could use this flaw to place core dumps into root-owned directories, potentially resulting in escalation of privileges.
Affected configurations
| CPE | Name | Operator | Version |
|---|---|---|---|
| linux:linux_kernel | linux linux kernel | eq | - |
CNA Affected
[
{
"product": "kernel",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "Not Known"
}
]
}
]References
access.redhat.com/security/cve/CVE-2021-3864
bugzilla.redhat.com/show_bug.cgi?id=2015046
lore.kernel.org/all/20211221021744.864115-1-longman%40redhat.com/
lore.kernel.org/all/20211226150310.GA992%401wt.eu/
lore.kernel.org/lkml/20211228170910.623156-1-wander%40redhat.com/
security-tracker.debian.org/tracker/CVE-2021-3864
www.openwall.com/lists/oss-security/2021/10/20/2
Social References
More
Related
7 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
6.9 Medium
AI Score
Confidence
High
0.0004 Low
EPSS
Percentile
5.1%