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TI-2021-22191 Aliases CVE-2021-47541

net/mlx4_en: Fix an use-after-free bug in mlx4_en_try_alloc_resources()

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
Partial Red Hat: 1 without a fix

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

Summary

In the Linux kernel, the following vulnerability has been resolved: net/mlx4_en: Fix an use-after-free bug in mlx4_en_try_alloc_resources() In mlx4_en_try_alloc_resources(), mlx4_en_copy_priv() is called and tmp->tx_cq will be freed on the error path of mlx4_en_copy_priv(). After that mlx4_en_alloc_resources() is called and there is a dereference of &tmp->tx_cq[t][i] in mlx4_en_alloc_resources(), which could lead to a use after free problem on failure of mlx4_en_copy_priv(). Fix this bug by adding a check of mlx4_en_copy_priv() This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_MLX4_EN=m show no new warnings, and our static analyzer no longer warns about this code.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00295 22nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 4.14.257, 4.19.220, 5.4.164 +3Red Hat: 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux4.7 and later4.14.257, 4.19.220, 5.4.164, 5.10.84, 5.15.7, 5.16Patch availableCNA
  • Linux VendorLinux Affected 4.7 and later Fixed in 4.14.257, 4.19.220, 5.4.164, 5.10.84, 5.15.7, 5.16 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*4.7 to before 4.14.257; 4.15 to before 4.19.220; 4.20 to before 5.4.164; 5.5 to before 5.10.84; 5.11 to before 5.15.7VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.7 to before 4.14.257; 4.15 to before 4.19.220; 4.20 to before 5.4.164; 5.5 to before 5.10.84; 5.11 to before 5.15.7 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 4.14.257, 4.19.220, 5.4.164, 5.10.84, 5.15.7, 5.16

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Not affected: 3 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-47541

References

Patch 6

  • 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