CVE-2022-49698

netfilter: use get_random_u32 instead of prandom

Published Feb 26, 2025 CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

netfilter: use get_random_u32 instead of prandom

bh might occur while updating per-cpu rnd_state from user context,
ie. local_out path.

BUG: using smp_processor_id() in preemptible [00000000] code: nginx/2725
caller is nft_ng_random_eval+0x24/0x54 [nft_numgen]
Call Trace:
check_preemption_disabled+0xde/0xe0
nft_ng_random_eval+0x24/0x54 [nft_numgen]

Use the random driver instead, this also avoids need for local prandom
state. Moreover, prandom now uses the random driver since d4150779e60f
("random32: use real rng for non-deterministic randomness").

Based on earlier patch from Pablo Neira.

Analysis

No analysis available yet

Remediation

No remediation available yet

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2022-54537 In the Linux kernel, the following vulnerability has been resolved: netfilter: use get_random_u32 instead of prandom bh might occur while updating per-cpu rnd_state from user context, ie. local_out path. BUG: using smp_processor_id() in preemptible [00000000] code: nginx/2725 caller is nft_ng_random_eval+0x24/0x54 [nft_numgen] Call Trace: check_preemption_disabled+0xde/0xe0 nft_ng_random_eval+0x24/0x54 [nft_numgen] Use the random driver instead, this also avoids need for local prandom state. Moreover, prandom now uses the random driver since d4150779e60f ("random32: use real rng for non-deterministic randomness"). Based on earlier patch from Pablo Neira.
Ubuntu USN Ubuntu USN USN-7990-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7990-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7990-3 Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7990-4 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-7990-5 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7990-6 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-8224-1 Linux kernel (BlueField) vulnerabilities
History
Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.19:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.19:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.19:rc3:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
Metrics cvssV3_1

{'score': 4.7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

Type Values Removed Values Added
CPEs cpe:/a:redhat:enterprise_linux:9
cpe:/o:redhat:enterprise_linux:9
Type Values Removed Values Added
First Time appeared Redhat
Redhat enterprise Linux
CPEs cpe:/o:redhat:enterprise_linux:8
Vendors & Products Redhat
Redhat enterprise Linux
Type Values Removed Values Added
Weaknesses CWE-362
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 4.7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'}

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: netfilter: use get_random_u32 instead of prandom bh might occur while updating per-cpu rnd_state from user context, ie. local_out path. BUG: using smp_processor_id() in preemptible [00000000] code: nginx/2725 caller is nft_ng_random_eval+0x24/0x54 [nft_numgen] Call Trace: check_preemption_disabled+0xde/0xe0 nft_ng_random_eval+0x24/0x54 [nft_numgen] Use the random driver instead, this also avoids need for local prandom state. Moreover, prandom now uses the random driver since d4150779e60f ("random32: use real rng for non-deterministic randomness"). Based on earlier patch from Pablo Neira.
Title netfilter: use get_random_u32 instead of prandom
References
Weaknesses
  • CWE-362

    Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

  • NVD-CWE-noinfo

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
May 11, 2026, 7:04 PM
Reserved
Feb 26, 2025, 2:21 AM
Status
Analyzed
Published
Feb 26, 2025, 7:01 AM
Modified
Jun 17, 2026, 5:18 AM
Severity
Moderate
Public date
Feb 26, 2025, 12:00 AM