CVE-2021-0920

CRITICALNVD 6.49.0
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2022-05-23), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 6.4 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, nvd
Trending — 5 sources updated this weekExploited in the wild
9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 1%CVSS: 6.4Exploit: cisa kev · ssvc activeExposed: 0

A fix is available — apply it.

In unix_scm_to_skb of af_unix.c, there is a possible use after free bug due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-196926917References: Upstream kernel

CVSS v3
6.4
EG Score
9.0(high)
EG Risk
81(Attend)
EG Risk 81/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity90% × 45%
Exploitation100% × 40%
Automatability0% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
1%
EPSS %ILE
56%
KEV
⚠ Exploited

Published

December 15, 2021

Last Modified

October 23, 2025

Advisory Details (3)

Auto-updated Jun 13, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: cisa.
cisa Patch Available🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-0920
generic

Android Security Bulletin—November 2021  |  Android Open Source Project

https://source.android.com/security/bulletin/2021-11-01
generic Patch Available

[SECURITY] [DLA 2843-1] linux security update

https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html

Patch Availability(19)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual (3.13.0.207.217) @ trusty2026-09-08ubuntu
ubuntulinux-image-lowlatency (4.4.0.223.230) @ xenial2026-09-08ubuntu
redhatkernel-0:2.6.32-754.47.1.el62022-04-19redhat
redhatkpatch-patch2022-04-13redhat
redhatkernel-0:3.10.0-1062.66.1.el72022-04-12redhat
redhatredhat-virtualization-host-0:4.3.22-20220330.1.el7_92022-04-07redhat
redhatkernel-0:3.10.0-693.99.1.el72022-03-29redhat
redhatkernel-0:3.10.0-957.92.1.el72022-03-29redhat
redhatkernel-0:3.10.0-514.99.1.el72022-03-29redhat
redhatredhat-virtualization-host-0:4.4.10-202203101736_8.52022-03-14redhat
redhatkernel-0:4.18.0-147.64.1.el8_12022-03-10redhat
redhatkernel-rt-0:4.18.0-348.20.1.rt7.150.el8_52022-03-10redhat
redhatkernel-0:4.18.0-348.20.1.el8_52022-03-10redhat
redhatkernel-0:4.18.0-305.40.1.el8_42022-03-08redhat
redhatkernel-rt-0:4.18.0-305.40.1.rt7.112.el8_42022-03-08redhat
redhatkernel-rt-0:4.18.0-193.75.1.rt13.125.el8_22022-02-22redhat
redhatkernel-0:4.18.0-193.75.1.el8_22022-02-22redhat
redhatkernel-rt-0:3.10.0-1160.59.1.rt56.1200.el72022-02-22redhat
redhatkernel-0:3.10.0-1160.59.1.el72022-02-22redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux5.10.46-4, 5.10.46-5, 5.10.70-1~bpo10+15.10.70-1
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux5.14.6-1
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux5.14.6-1
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux5.14.6-1
Debian:9(1)
PackageVulnerable rangeFixed inDependents
linux4.9.107-1 ... 4.9.88-1~bpo8+1 (68 versions)4.9.290-1

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(5)

Data Freshness Timeline

(refreshed 109× in last 7d / 460× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 1,501 total refreshes for this CVE.

  1. 2026-09-08 09:03 UTCVendor advisory
  2. 2026-09-08 09:03 UTCGHSA enrichment
  3. 2026-09-08 05:20 UTCVendor advisory
  4. 2026-09-08 05:20 UTCGHSA enrichment
  5. 2026-09-08 01:40 UTCVendor advisory
  6. 2026-09-08 01:39 UTCGHSA enrichment
  7. 2026-09-07 21:58 UTCVendor advisory
  8. 2026-09-07 21:58 UTCGHSA enrichment
  9. 2026-09-07 18:17 UTCEG score recompute
  10. 2026-09-07 18:17 UTCVendor advisory
  11. 2026-09-07 18:16 UTCGHSA enrichment
  12. 2026-09-07 15:58 UTCEPSS rescore
  13. 2026-09-07 14:35 UTCVendor advisory
  14. 2026-09-07 14:35 UTCGHSA enrichment
  15. 2026-09-07 10:50 UTCVendor advisory
  16. 2026-09-07 10:49 UTCGHSA enrichment
  17. 2026-09-07 07:07 UTCVendor advisory
  18. 2026-09-07 07:07 UTCGHSA enrichment
  19. 2026-09-07 03:25 UTCVendor advisory
  20. 2026-09-07 03:25 UTCGHSA enrichment
  21. 2026-09-06 23:43 UTCVendor advisory
  22. 2026-09-06 23:43 UTCGHSA enrichment
  23. 2026-09-06 20:02 UTCVendor advisory
  24. 2026-09-06 20:02 UTCGHSA enrichment
  25. 2026-09-06 16:21 UTCEG score recompute
Show 75 more
  1. 2026-09-06 16:21 UTCVendor advisory
  2. 2026-09-06 16:21 UTCGHSA enrichment
  3. 2026-09-06 13:44 UTCEPSS rescore
  4. 2026-09-06 13:44 UTCEPSS rescore
  5. 2026-09-06 12:39 UTCVendor advisory
  6. 2026-09-06 12:39 UTCGHSA enrichment
  7. 2026-09-06 08:58 UTCVendor advisory
  8. 2026-09-06 08:58 UTCGHSA enrichment
  9. 2026-09-06 05:17 UTCVendor advisory
  10. 2026-09-06 05:17 UTCGHSA enrichment
  11. 2026-09-06 01:35 UTCVendor advisory
  12. 2026-09-06 01:35 UTCGHSA enrichment
  13. 2026-09-05 21:54 UTCVendor advisory
  14. 2026-09-05 21:54 UTCGHSA enrichment
  15. 2026-09-05 18:13 UTCEG score recompute
  16. 2026-09-05 18:13 UTCVendor advisory
  17. 2026-09-05 18:13 UTCGHSA enrichment
  18. 2026-09-05 15:25 UTCEPSS rescore
  19. 2026-09-05 14:31 UTCVendor advisory
  20. 2026-09-05 14:30 UTCGHSA enrichment
  21. 2026-09-05 10:49 UTCVendor advisory
  22. 2026-09-05 10:49 UTCGHSA enrichment
  23. 2026-09-05 07:08 UTCVendor advisory
  24. 2026-09-05 07:08 UTCGHSA enrichment
  25. 2026-09-05 03:27 UTCVendor advisory
  26. 2026-09-05 03:27 UTCGHSA enrichment
  27. 2026-09-04 23:46 UTCVendor advisory
  28. 2026-09-04 23:46 UTCGHSA enrichment
  29. 2026-09-04 20:05 UTCVendor advisory
  30. 2026-09-04 20:05 UTCGHSA enrichment
  31. 2026-09-04 17:38 UTCCISA KEV update
  32. 2026-09-04 16:23 UTCEG score recompute
  33. 2026-09-04 16:23 UTCVendor advisory
  34. 2026-09-04 16:23 UTCGHSA enrichment
  35. 2026-09-04 13:57 UTCEPSS rescore
  36. 2026-09-04 12:41 UTCVendor advisory
  37. 2026-09-04 12:41 UTCGHSA enrichment
  38. 2026-09-04 09:00 UTCVendor advisory
  39. 2026-09-04 09:00 UTCGHSA enrichment
  40. 2026-09-04 05:18 UTCEG score recompute
  41. 2026-09-04 05:18 UTCVendor advisory
  42. 2026-09-04 05:18 UTCGHSA enrichment
  43. 2026-09-04 05:03 UTCEPSS rescore
  44. 2026-09-04 01:36 UTCVendor advisory
  45. 2026-09-04 01:36 UTCGHSA enrichment
  46. 2026-09-03 21:54 UTCVendor advisory
  47. 2026-09-03 21:54 UTCGHSA enrichment
  48. 2026-09-03 18:13 UTCVendor advisory
  49. 2026-09-03 18:13 UTCGHSA enrichment
  50. 2026-09-03 14:32 UTCVendor advisory
  51. 2026-09-03 14:32 UTCGHSA enrichment
  52. 2026-09-03 10:50 UTCVendor advisory
  53. 2026-09-03 10:50 UTCGHSA enrichment
  54. 2026-09-03 07:07 UTCVendor advisory
  55. 2026-09-03 07:06 UTCGHSA enrichment
  56. 2026-09-03 03:22 UTCVendor advisory
  57. 2026-09-03 03:21 UTCGHSA enrichment
  58. 2026-09-02 23:37 UTCVendor advisory
  59. 2026-09-02 23:37 UTCGHSA enrichment
  60. 2026-09-02 19:56 UTCVendor advisory
  61. 2026-09-02 19:56 UTCGHSA enrichment
  62. 2026-09-02 17:33 UTCCISA KEV update
  63. 2026-09-02 16:14 UTCEG score recompute
  64. 2026-09-02 16:14 UTCVendor advisory
  65. 2026-09-02 16:14 UTCGHSA enrichment
  66. 2026-09-02 14:08 UTCEPSS rescore
  67. 2026-09-02 12:33 UTCVendor advisory
  68. 2026-09-02 12:33 UTCGHSA enrichment
  69. 2026-09-02 08:51 UTCVendor advisory
  70. 2026-09-02 08:51 UTCGHSA enrichment
  71. 2026-09-02 05:10 UTCVendor advisory
  72. 2026-09-02 05:10 UTCGHSA enrichment
  73. 2026-09-02 01:29 UTCVendor advisory
  74. 2026-09-02 01:29 UTCGHSA enrichment
  75. 2026-09-01 21:46 UTCVendor advisory

Frequently asked(6)

What is CVE-2021-0920?
CVE-2021-0920 is a critical vulnerability published on December 15, 2021. In unixscmtoskb of afunix.c, there is a possible use after free bug due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID:…
When was CVE-2021-0920 disclosed?
CVE-2021-0920 was first published in the National Vulnerability Database on December 15, 2021, with the most recent update on October 23, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-0920 actively exploited?
Yes. CISA added CVE-2021-0920 to the Known Exploited Vulnerabilities catalog on May 23, 2022, affecting Android Kernel. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2021-0920?
CVE-2021-0920 has a CVSS v3 base score of 6.4 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2021-0920?
CVE-2021-0920 affects Android Kernel. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2021-0920?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-0920, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-0920

Explore →

Is Your Infrastructure Affected by CVE-2021-0920?

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