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  4. CVE 2021 46913 netfilter nftables clone set element expression
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Back to active CVEs
High · CVSS 7.8CVE-2021-46913

netfilter: nftables: clone set element expression templateCVE-2021-46913

Answer in brief

CVE-2021-46913 records a High severity (CVSS 7.8) vulnerability in netfilter: nftables: clone set element expression template. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Feb 27, 2024Updated Aug 5, 2026Source checked Nov 5, 2026First seen by HOL Aug 4, 2026Material review Aug 5, 2026
Upstream Advisory

Key facts

Risk
High · CVSS 7.8
Exploitation
Not marked as known exploited
Affected software
3 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Affected products and reported versions
ProductAffected versionsFixed versions
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*Not reportedNot reported
Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Linux/Linuxgeneric>=4094445229760d0d31a4190dfe88fe815c9fc34e <e51ff3ffc316377cca21de8b80404eed0c37b3c3 || >=4094445229760d0d31a4190dfe88fe815c9fc34e <47d8de3c226574a3ddb8b87d0c152028d1bafef4 || >=4094445229760d0d31a4190dfe88fe815c9fc34e <4d8f9065830e526c83199186c5f56a6514f457d2e51ff3ffc316377cca21de8b80404eed0c37b3c3, 47d8de3c226574a3ddb8b87d0c152028d1bafef4, 4d8f9065830e526c83199186c5f56a6514f457d2
Linux/Linuxgeneric5.7Not reported

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
  2. 2Review the reported fix. Update Linux/Linux to e51ff3ffc316377cca21de8b80404eed0c37b3c3 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Feb 27, 2024

    Evidence: source:cvelist:source_dates:source-dates:record
  2. Source modified

    Aug 5, 2026

    Evidence: source:cvelist:source_dates:source-dates:record
  3. First seen by HOL

    Aug 4, 2026

Sources and claim methodology

  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
Upstream source description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nftables: clone set element expression template memcpy() breaks when using connlimit in set elements. Use nft_expr_clone() to initialize the connlimit expression list, otherwise connlimit garbage collector crashes when walking on the list head copy. [ 493.064656] Workqueue: events_power_efficient nft_rhash_gc [nf_tables] [ 493.064685] RIP: 0010:find_or_evict+0x5a/0x90 [nf_conncount] [ 493.064694] Code: 2b 43 40 83 f8 01 77 0d 48 c7 c0 f5 ff ff ff 44 39 63 3c 75 df 83 6d 18 01 48 8b 43 08 48 89 de 48 8b 13 48 8b 3d ee 2f 00 00 <48> 89 42 08 48 89 10 48 b8 00 01 00 00 00 00 ad de 48 89 03 48 83 [ 493.064699] RSP: 0018:ffffc90000417dc0 EFLAGS: 00010297 [ 493.064704] RAX: 0000000000000000 RBX: ffff888134f38410 RCX: 0000000000000000 [ 493.064708] RDX: 0000000000000000 RSI: ffff888134f38410 RDI: ffff888100060cc0 [ 493.064711] RBP: ffff88812ce594a8 R08: ffff888134f38438 R09: 00000000ebb9025c [ 493.064714] R10: ffffffff8219f838 R11: 0000000000000017 R12: 0000000000000001 [ 493.064718] R13: ffffffff82146740 R14: ffff888134f38410 R15: 0000000000000000 [ 493.064721] FS: 0000000000000000(0000) GS:ffff88840e440000(0000) knlGS:0000000000000000 [ 493.064725] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 493.064729] CR2: 0000000000000008 CR3: 00000001330aa002 CR4: 00000000001706e0 [ 493.064733] Call Trace: [ 493.064737] nf_conncount_gc_list+0x8f/0x150 [nf_conncount] [ 493.064746] nft_rhash_gc+0x106/0x390 [nf_tables]

Quoted source text, attributed separately from HOL analysis.

Record context

Vulnerability class
Tool Poisoning
EPSS
Not reported
CWE IDs
NVD-CWE-noinfo
Source
CVE List V5
Source checked
Nov 5, 2026
References
3 linked sources
Open source record