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TI-2021-21911 Aliases CVE-2021-47252GHSA-cwj6-5v55-7mj7

batman-adv: Avoid WARN_ON timing related checks

Priority LOW 24Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

In the Linux kernel, the following vulnerability has been resolved: batman-adv: Avoid WARN_ON timing related checks The soft/batadv interface for a queued OGM can be changed during the time the OGM was queued for transmission and when the OGM is actually transmitted by the worker. But WARN_ON must be used to denote kernel bugs and not to print simple warnings. A warning can simply be printed using pr_warn.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00226 13th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 4.4.293, 4.9.274, 4.14.238 +5

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
LinuxLinux3.14 and later4.4.293, 4.9.274, 4.14.238, 4.19.196, 5.4.128, 5.10.46, 5.12.13, 5.13Patch availableCNA
  • Linux VendorLinux Affected 3.14 and later Fixed in 4.4.293, 4.9.274, 4.14.238, 4.19.196, 5.4.128, 5.10.46, 5.12.13, 5.13 Patch available CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*3.14 to before 4.4.293; 4.5 to before 4.9.274; 4.10 to before 4.14.238; 4.15 to before 4.19.196; 4.20 to before 5.4.128; 5.5 to before 5.10.46; 5.11 to before 5.12.13VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*5.13 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*5.13 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*5.13 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*5.13 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*5.13 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*5.13 rc6VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 3.14 to before 4.4.293; 4.5 to before 4.9.274; 4.10 to before 4.14.238; 4.15 to before 4.19.196; 4.20 to before 5.4.128; 5.5 to before 5.10.46; 5.11 to before 5.12.13 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:* Versions 5.13 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:* Versions 5.13 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:* Versions 5.13 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:* Versions 5.13 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:* Versions 5.13 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:* Versions 5.13 rc6 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 4.4.293, 4.9.274, 4.14.238, 4.19.196, 5.4.128, 5.10.46, 5.12.13, 5.13

Vendor assessments

Red Hat

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

Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-47252
  2. 2026-10-03 Alias added: GHSA-cwj6-5v55-7mj7

References

  • 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