ReviewHigh

CVE-2021-41864

linux kernel, fedora

prealloc_elems_and_freelist in kernel/bpf/stackmap.c in the Linux kernel before 5.14.12 allows unprivileged users to trigger an eBPF multiplication integer overflow with a resultant out-of-bounds write.

CVSS
7.8
EPSS
0.41%
34.0% percentile
CISA KEV
Not listed
Published
2021.10.02
PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.41%
Technical severityCVSS 7.8

Vulnerability overview

prealloc_elems_and_freelist in kernel/bpf/stackmap.c in the Linux kernel before 5.14.12 allows unprivileged users to trigger an eBPF multiplication integer overflow with a resultant out-of-bounds write.

Affected product and versions

Product
linux kernel, fedora
Affected versions
>= 4.6 < 4.9.287, >= 4.10 < 4.14.251, >= 4.15 < 4.19.211, >= 4.20 < 5.4.153, >= 5.5 < 5.10.73, >= 5.11 < 5.14.12, 33, 34, 35, 9.0, 10.0
Fixed versions
4.9.287, 4.14.251, 4.19.211, 5.4.153, 5.10.73, 5.14.12

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that linux kernel, fedora and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-190