CVE-2021-0920

MEDIUMNVD 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
6.4
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS: 1%CVSS: 6.4Exploit: NoneExposed: 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
53.1%
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-image-lowlatency (4.4.0.223.230) @ xenial2026-07-22ubuntu
ubuntulinux-virtual (3.13.0.207.217) @ trusty2026-07-22ubuntu
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-0:3.10.0-957.92.1.el72022-03-29redhat
redhatkernel-0:3.10.0-693.99.1.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-0:4.18.0-348.20.1.el8_52022-03-10redhat
redhatkernel-rt-0:4.18.0-348.20.1.rt7.150.el8_52022-03-10redhat
redhatkernel-0:4.18.0-147.64.1.el8_12022-03-10redhat
redhatkernel-rt-0:4.18.0-305.40.1.rt7.112.el8_42022-03-08redhat
redhatkernel-0:4.18.0-305.40.1.el8_42022-03-08redhat
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
redhatkernel-rt-0:4.18.0-193.75.1.rt13.125.el8_22022-02-22redhat

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.

Weakness Classification(2)

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

Additional Vendor Advisories

(8)

Data Freshness Timeline

(refreshed 106× in last 7d / 452× 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 813 total refreshes for this CVE.

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

Frequently asked(6)

What is CVE-2021-0920?
CVE-2021-0920 is a medium 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

Explore the affected products and dependency analysis for CVE-2021-0920

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