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TI-2021-09757 Aliases CVE-2021-28691GHSA-5gvc-4qph-j93r

Use after free in Linux

Priority LOW 34CWE-416Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

Summary

Guest triggered use-after-free in Linux xen-netback A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux netback when the backend is destroyed, as the kernel thread associated with queue 0 will have already exited and thus the call to kthread_stop will be performed against a stale pointer.

Why it matters now

EPSS 0.00364 30th percentileScored 2026-11-07
Fix Fixed Linux (Linux): next of 5.12.2

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.5.0 and laternext of 5.12.2Patch availableCNA
  • Linux VendorLinux Affected 5.5.0 and later Fixed in next of 5.12.2 Patch available CNA

CPE configurations NVD · 19

CPEVersionsRoleVendor
cpe:2.3:a:netapp:solidfire_baseboard_management_controller:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.5.0 to before 5.10.43VulnerableLinux
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
  • cpe:2.3:a:netapp:solidfire_baseboard_management_controller:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.5.0 to before 5.10.43 Vulnerable ·Linux
  • cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
Show 9 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h300e:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h500e:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h700e:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:*not specified by NVDRunning onNetApp
  • cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h300e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h500e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h700e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
  • cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp

Remediation

  • Fix · CNA Linux (Linux) Fixed in next of 5.12.2

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-28691
  2. 2026-10-03 Alias added: GHSA-5gvc-4qph-j93r

References

Advisory 3

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

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