Linux kernel eBPF bitwise ops ALU32 bounds tracking (Linux Linux kernel)
At a glance
- Source
- NVD
- EPSS
- EPSS 27.38 % · percentile 98 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- canonical
- NVD status
- Modified
Description
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).
Weaknesses (CWE)
References
- https://ubuntu.com/security/notices/USN-4950-1
- https://ubuntu.com/security/notices/USN-4949-1
- https://www.openwall.com/lists/oss-security/2021/05/11/11
- https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=049c4e13714ecbca567b4d5f6d563f05d431c80e
- https://www.zerodayinitiative.com/advisories/ZDI-21-606/
- https://security.netapp.com/advisory/ntap-20210716-0004/
- http://packetstormsecurity.com/files/164015/Linux-eBPF-ALU32-32-bit-Invalid-Bounds-Tracking-Local-Privilege-Escalation.html
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H | canonical |
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H | NVD · security@ubuntu.com (Secondary) |
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · nvd@nist.gov (Primary) |
| CVSS 2.0 | HIGH 7.2 | AV:L/AC:L/Au:N/C:C/I:C/A:C | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2021-26812
- GCVE · GCVE-0-2021-3490
CERT-FR advisories
- CERTFR-2021-AVI-751 — Multiples vulnérabilités dans Google Android · cert.ssi.gouv.fr
- CERTFR-2021-AVI-500 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2021-AVI-469 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2021-AVI-372 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.10 < 5.10.37cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.11 < 5.11.21cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.12 < 5.12.4cpe:2.3:o:linux:linux_kernel:5.13:-:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*cpe:2.3:o:canonical:ubuntu_linux:20.10:*:*:*:*:*:*:*cpe:2.3:o:canonical:ubuntu_linux:21.04:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux kernel | affected trunk < v5.13-rc4 ; affected linux-5.12.y < v5.12.4 ; affected linux-5.11.y < v5.11.21 ; affected linux-5.10.y < v5.10.37 ; affected v5.7-rc1 < 5.7* |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |