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TI-2021-00657 Aliases CVE-2021-0920GHSA-r93f-j2vf-vmc4

Use after free in Android

Priority CRITICAL 88Exploited in the wildCWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
High
User interaction
None
Attack complexity
High
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

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

Why it matters now

Exploitation Active In CISA KEV since 2022-05-23CISA due date 2022-06-13
EPSS 0.00867 58th percentileScored 2026-11-07
Fix Fixed Red Hat: 24 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Active
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—AndroidAndroid kernel—No fix listedCNA
  • Android Vendor— Affected Android kernel Fixed in — No fix listed CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*up to 5.13VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:*5.14 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:*5.14 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.14:rc3:*:*:*:*:*:*5.14 rc3VulnerableLinux
cpe:2.3:o:google:android:-:*:*:*:*:*:*:*not specified by NVDVulnerableGoogle
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions up to 5.13 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:* Versions 5.14 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:* Versions 5.14 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.14:rc3:*:*:*:*:*:* Versions 5.14 rc3 Vulnerable ·Linux
  • cpe:2.3:o:google:android:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Google
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian

Remediation

Red Hat 24 advisories

  • RHSA-2022:1417 Released 2022-04-19 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Server (v. 6 ELS) kernel-2.6.32-754.47.1.el6, kernel-abi-whitelists-2.6.32-754.47.1.el6, kernel-debug-2.6.32-754.47.1.el6 +7
    • Red Hat Enterprise Linux Server Optional (v. 6 ELS) python-perf-2.6.32-754.47.1.el6
  • RHSA-2022:1373 Released 2022-04-13 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux Server E4S (v. 7.7) kpatch-patch-3_10_0-1062_49_1-1-6.el7, kpatch-patch-3_10_0-1062_51_1-1-6.el7, kpatch-patch-3_10_0-1062_52_2-1-5.el7 +5
  • RHSA-2022:1324 Released 2022-04-12 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux Server AUS (v. 7.7) bpftool-3.10.0-1062.66.1.el7, kernel-3.10.0-1062.66.1.el7, kernel-abi-whitelists-3.10.0-1062.66.1.el7 +8
    • Red Hat Enterprise Linux Server E4S (v. 7.7) bpftool-3.10.0-1062.66.1.el7, kernel-3.10.0-1062.66.1.el7, kernel-abi-whitelists-3.10.0-1062.66.1.el7 +9
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.7) kernel-tools-libs-devel-3.10.0-1062.66.1.el7
    • Red Hat Enterprise Linux Server Optional E4S (v. 7.7) kernel-debug-devel-3.10.0-1062.66.1.el7, kernel-tools-libs-devel-3.10.0-1062.66.1.el7
    • Red Hat Enterprise Linux Server Optional TUS (v. 7.7) kernel-tools-libs-devel-3.10.0-1062.66.1.el7
    • Red Hat Enterprise Linux Server TUS (v. 7.7) bpftool-3.10.0-1062.66.1.el7, kernel-3.10.0-1062.66.1.el7, kernel-abi-whitelists-3.10.0-1062.66.1.el7 +8
Show 21 more Red Hat advisories
  • RHSA-2022:1263 Released 2022-04-07 · Red Hat rating Important
    RHV-H security update (redhat-virtualization-host) 4.3.22
    • RHEL 7-based RHEV-H for RHEV 4 (build requirements) redhat-virtualization-host-4.3.22-20220330.1.el7_9, redhat-virtualization-host-image-update-4.3.22-20220330.1.el7_9
    • Red Hat Virtualization 4 Hypervisor for RHEL 7 redhat-virtualization-host-4.3.22-20220330.1.el7_9, redhat-virtualization-host-image-update-4.3.22-20220330.1.el7_9
  • RHSA-2022:1107 Released 2022-03-29 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Server AUS (v. 7.6) bpftool-3.10.0-957.92.1.el7, kernel-3.10.0-957.92.1.el7, kernel-abi-whitelists-3.10.0-957.92.1.el7 +8
    • Red Hat Enterprise Linux Server E4S (v. 7.6) kernel-3.10.0-957.92.1.el7, kernel-abi-whitelists-3.10.0-957.92.1.el7, kernel-bootwrapper-3.10.0-957.92.1.el7 +8
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.6) kernel-tools-libs-devel-3.10.0-957.92.1.el7
    • Red Hat Enterprise Linux Server Optional E4S (v. 7.6) kernel-debug-devel-3.10.0-957.92.1.el7, kernel-tools-libs-devel-3.10.0-957.92.1.el7
    • Red Hat Enterprise Linux Server Optional TUS (v. 7.6) kernel-tools-libs-devel-3.10.0-957.92.1.el7
    • Red Hat Enterprise Linux Server TUS (v. 7.6) bpftool-3.10.0-957.92.1.el7, kernel-3.10.0-957.92.1.el7, kernel-abi-whitelists-3.10.0-957.92.1.el7 +8
  • RHSA-2022:1103 Released 2022-03-29 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux Server E4S (v. 7.6) kpatch-patch-3_10_0-957_72_1-1-6.el7, kpatch-patch-3_10_0-957_76_1-1-6.el7, kpatch-patch-3_10_0-957_78_2-1-5.el7 +4
  • RHSA-2022:1104 Released 2022-03-29 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Server AUS (v. 7.4) kernel-3.10.0-693.99.1.el7, kernel-abi-whitelists-3.10.0-693.99.1.el7, kernel-debug-3.10.0-693.99.1.el7 +7
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.4) kernel-tools-libs-devel-3.10.0-693.99.1.el7
  • RHSA-2022:1106 Released 2022-03-29 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Server AUS (v. 7.3) kernel-3.10.0-514.99.1.el7, kernel-abi-whitelists-3.10.0-514.99.1.el7, kernel-debug-3.10.0-514.99.1.el7 +7
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.3) kernel-tools-libs-devel-3.10.0-514.99.1.el7
  • RHSA-2022:0958 Released 2022-03-17 · Red Hat rating Important
    kpatch-patch-4_18_0-147_58_1 security and bug fix update
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.1) kpatch-patch-4_18_0-147_58_1-1-1.el8_1
  • RHSA-2022:0849 Released 2022-03-14 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS (v. 8) kpatch-patch-4_18_0-348-1-3.el8, kpatch-patch-4_18_0-348_12_2-1-1.el8_5, kpatch-patch-4_18_0-348_2_1-1-2.el8_5 +1
  • RHSA-2022:0851 Released 2022-03-14 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.1) kpatch-patch-4_18_0-147_44_1-1-10.el8_1, kpatch-patch-4_18_0-147_48_1-1-7.el8_1, kpatch-patch-4_18_0-147_51_1-1-6.el8_1 +6
  • RHSA-2022:0841 Released 2022-03-14 · Red Hat rating Important
    Red Hat Virtualization Host security and bug fix update [ovirt-4.4.10] Async #1
    • Red Hat Virtualization 4 Hypervisor for RHEL 8 redhat-virtualization-host-4.4.10-202203101736_8.5, redhat-virtualization-host-image-update-4.4.10-202203101736_8.5
  • RHSA-2022:0825 Released 2022-03-10 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder (v. 8) kernel-tools-libs-devel-4.18.0-348.20.1.el8_5
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-348.20.1.el8_5, kernel-4.18.0-348.20.1.el8_5, kernel-abi-stablelists-4.18.0-348.20.1.el8_5 +19
  • RHSA-2022:0823 Released 2022-03-10 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.1) bpftool-4.18.0-147.64.1.el8_1, kernel-4.18.0-147.64.1.el8_1, kernel-abi-whitelists-4.18.0-147.64.1.el8_1 +14
  • RHSA-2022:0819 Released 2022-03-10 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt-4.18.0-348.20.1.rt7.150.el8_5, kernel-rt-core-4.18.0-348.20.1.rt7.150.el8_5, kernel-rt-debug-4.18.0-348.20.1.rt7.150.el8_5 +9
    • Red Hat Enterprise Linux for Real Time (v. 8) kernel-rt-4.18.0-348.20.1.rt7.150.el8_5, kernel-rt-core-4.18.0-348.20.1.rt7.150.el8_5, kernel-rt-debug-4.18.0-348.20.1.rt7.150.el8_5 +7
  • RHSA-2022:0777 Released 2022-03-08 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS EUS (v.8.4) bpftool-4.18.0-305.40.1.el8_4, kernel-4.18.0-305.40.1.el8_4, kernel-abi-stablelists-4.18.0-305.40.1.el8_4 +19
    • Red Hat Enterprise Linux CRB EUS (v.8.4) kernel-tools-libs-devel-4.18.0-305.40.1.el8_4
  • RHSA-2022:0772 Released 2022-03-08 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS EUS (v.8.4) kpatch-patch-4_18_0-305-1-11.el8, kpatch-patch-4_18_0-305_10_2-1-8.el8_4, kpatch-patch-4_18_0-305_12_1-1-7.el8_4 +8
  • RHSA-2022:0771 Released 2022-03-08 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux NFV EUS (v.8.4) kernel-rt-4.18.0-305.40.1.rt7.112.el8_4, kernel-rt-core-4.18.0-305.40.1.rt7.112.el8_4, kernel-rt-debug-4.18.0-305.40.1.rt7.112.el8_4 +9
    • Red Hat Enterprise Linux RT EUS (v.8.4) kernel-rt-4.18.0-305.40.1.rt7.112.el8_4, kernel-rt-core-4.18.0-305.40.1.rt7.112.el8_4, kernel-rt-debug-4.18.0-305.40.1.rt7.112.el8_4 +7
  • RHSA-2022:0620 Released 2022-02-22 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux Client (v. 7) bpftool-3.10.0-1160.59.1.el7, kernel-3.10.0-1160.59.1.el7, kernel-abi-whitelists-3.10.0-1160.59.1.el7 +8
    • Red Hat Enterprise Linux Client Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.59.1.el7
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.59.1.el7
    • Red Hat Enterprise Linux Server (v. 7) bpftool-3.10.0-1160.59.1.el7, kernel-3.10.0-1160.59.1.el7, kernel-abi-whitelists-3.10.0-1160.59.1.el7 +11
    • Red Hat Enterprise Linux Server Optional (v. 7) kernel-debug-devel-3.10.0-1160.59.1.el7, kernel-tools-libs-devel-3.10.0-1160.59.1.el7
    • Red Hat Enterprise Linux Workstation (v. 7) bpftool-3.10.0-1160.59.1.el7, kernel-3.10.0-1160.59.1.el7, kernel-abi-whitelists-3.10.0-1160.59.1.el7 +8
    • Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.59.1.el7
  • RHSA-2022:0622 Released 2022-02-22 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux for Real Time (v. 7) kernel-rt-3.10.0-1160.59.1.rt56.1200.el7, kernel-rt-debug-3.10.0-1160.59.1.rt56.1200.el7, kernel-rt-debug-devel-3.10.0-1160.59.1.rt56.1200.el7 +4
    • Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt-3.10.0-1160.59.1.rt56.1200.el7, kernel-rt-debug-3.10.0-1160.59.1.rt56.1200.el7, kernel-rt-debug-devel-3.10.0-1160.59.1.rt56.1200.el7 +7
  • RHSA-2022:0636 Released 2022-02-22 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat CodeReady Linux Builder EUS (v. 8.2) kernel-tools-libs-devel-4.18.0-193.75.1.el8_2
    • Red Hat Enterprise Linux BaseOS EUS (v. 8.2) bpftool-4.18.0-193.75.1.el8_2, kernel-4.18.0-193.75.1.el8_2, kernel-abi-whitelists-4.18.0-193.75.1.el8_2 +19
  • RHSA-2022:0629 Released 2022-02-22 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux Real Time EUS (v. 8.2) kernel-rt-4.18.0-193.75.1.rt13.125.el8_2, kernel-rt-core-4.18.0-193.75.1.rt13.125.el8_2, kernel-rt-debug-4.18.0-193.75.1.rt13.125.el8_2 +7
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 8.2) kernel-rt-4.18.0-193.75.1.rt13.125.el8_2, kernel-rt-core-4.18.0-193.75.1.rt13.125.el8_2, kernel-rt-debug-4.18.0-193.75.1.rt13.125.el8_2 +9
  • RHSA-2022:0592 Released 2022-02-22 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux Server (v. 7) kpatch-patch-3_10_0-1160_21_1-1-9.el7, kpatch-patch-3_10_0-1160_24_1-1-7.el7, kpatch-patch-3_10_0-1160_25_1-1-7.el7 +7
  • RHSA-2022:0590 Released 2022-02-22 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS EUS (v. 8.2) kpatch-patch-4_18_0-193_46_1-1-9.el8_2, kpatch-patch-4_18_0-193_47_1-1-9.el8_2, kpatch-patch-4_18_0-193_51_1-1-6.el8_2 +7

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
RHEL 7-based RHEV-H for RHEV 4 (build requirements)Fixed RHSA-2022:1263
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2022:0825
Red Hat CodeReady Linux Builder EUS (v. 8.2)Fixed RHSA-2022:0636
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2022:0825, RHSA-2022:0849
Red Hat Enterprise Linux BaseOS E4S (v. 8.1)Fixed RHSA-2022:0823, RHSA-2022:0851, RHSA-2022:0958
Red Hat Enterprise Linux BaseOS EUS (v. 8.2)Fixed RHSA-2022:0590, RHSA-2022:0636
Red Hat Enterprise Linux BaseOS EUS (v.8.4)Fixed RHSA-2022:0772, RHSA-2022:0777
Red Hat Enterprise Linux CRB EUS (v.8.4)Fixed RHSA-2022:0777
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2022:0620
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2022:0620
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2022:0620
Red Hat Enterprise Linux NFV EUS (v.8.4)Fixed RHSA-2022:0771
Red Hat Enterprise Linux RT EUS (v.8.4)Fixed RHSA-2022:0771
Red Hat Enterprise Linux Real Time EUS (v. 8.2)Fixed RHSA-2022:0629
Red Hat Enterprise Linux Real Time for NFV (v. 8)Fixed RHSA-2022:0819
Red Hat Enterprise Linux Real Time for NFV EUS (v. 8.2)Fixed RHSA-2022:0629
Red Hat Enterprise Linux Server (v. 6 ELS)Fixed RHSA-2022:1417
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2022:0592, RHSA-2022:0620
Red Hat Enterprise Linux Server AUS (v. 7.3)Fixed RHSA-2022:1106
Red Hat Enterprise Linux Server AUS (v. 7.4)Fixed RHSA-2022:1104
Red Hat Enterprise Linux Server AUS (v. 7.6)Fixed RHSA-2022:1107
Red Hat Enterprise Linux Server AUS (v. 7.7)Fixed RHSA-2022:1324
Red Hat Enterprise Linux Server E4S (v. 7.6)Fixed RHSA-2022:1103, RHSA-2022:1107
Red Hat Enterprise Linux Server E4S (v. 7.7)Fixed RHSA-2022:1324, RHSA-2022:1373
Red Hat Enterprise Linux Server Optional (v. 6 ELS)Fixed RHSA-2022:1417
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2022:0620
Red Hat Enterprise Linux Server Optional AUS (v. 7.3)Fixed RHSA-2022:1106
Red Hat Enterprise Linux Server Optional AUS (v. 7.4)Fixed RHSA-2022:1104
Red Hat Enterprise Linux Server Optional AUS (v. 7.6)Fixed RHSA-2022:1107
Red Hat Enterprise Linux Server Optional AUS (v. 7.7)Fixed RHSA-2022:1324
Red Hat Enterprise Linux Server Optional E4S (v. 7.6)Fixed RHSA-2022:1107
Red Hat Enterprise Linux Server Optional E4S (v. 7.7)Fixed RHSA-2022:1324
Red Hat Enterprise Linux Server Optional TUS (v. 7.6)Fixed RHSA-2022:1107
Red Hat Enterprise Linux Server Optional TUS (v. 7.7)Fixed RHSA-2022:1324
Red Hat Enterprise Linux Server TUS (v. 7.6)Fixed RHSA-2022:1107
Red Hat Enterprise Linux Server TUS (v. 7.7)Fixed RHSA-2022:1324
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2022:0620
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2022:0620
Red Hat Enterprise Linux for Real Time (v. 7)Fixed RHSA-2022:0622
Red Hat Enterprise Linux for Real Time (v. 8)Fixed RHSA-2022:0819
Red Hat Enterprise Linux for Real Time for NFV (v. 7)Fixed RHSA-2022:0622
Red Hat Virtualization 4 Hypervisor for RHEL 7Fixed RHSA-2022:1263
Red Hat Virtualization 4 Hypervisor for RHEL 8Fixed RHSA-2022:0841
Not affected: 3 products
  • RHEL 7-based RHEV-H for RHEV 4 (build requirements)
  • RHEL 8-based RHEV-H for RHEV 4 (build requirements)
  • Red Hat Enterprise Linux 9

Timeline

  1. 2022-05-23 Added to CISA KEV
  2. 2026-10-02 Threatist record created from CVE-2021-0920
  3. 2026-10-03 Alias added: GHSA-r93f-j2vf-vmc4

References

Advisory 3

  • TI-2025-30821 Use after free in Google Android KEVCVSS 3.1HIGH 8.8
  • TI-2023-17777 Improper privilege management in Google Android KEVCVSS 3.1HIGH 8.8
  • TI-2025-30872 Integer overflow in Google Android KEVCVSS 3.1HIGH 8.4
  • TI-2024-21766 there is a possible way to bypass due to a logic error in the code. KEVCVSS 3.1HIGH 8.1
  • TI-2025-30849 Missing authentication in Google Android KEVCVSS 3.1HIGH 7.8
  • TI-2024-24518 net: fix __dst_negative_advice() race KEVCVSS 3.1HIGH 7.8
See all 77 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences