CVE-2021-47174

MEDIUMNVD 5.55.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

Score 5.5 from GitHub Security Advisory published 2024-03-25. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
5.5EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 5.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nft_set_pipapo_avx2: Add irq_fpu_usable() check, fallback to non-AVX2 version

Arturo reported this backtrace:

[709732.358791] WARNING: CPU: 3 PID: 456 at arch/x86/kernel/fpu/core.c:128 kernel_fpu_begin_mask+0xae/0xe0 [709732.358793] Modules linked in: binfmt_misc nft_nat nft_chain_nat nf_nat nft_counter nft_ct nf_tables nf_conntrack_netlink nfnetlink 8021q garp stp mrp llc vrf intel_rapl_msr intel_rapl_common skx_edac nfit libnvdimm ipmi_ssif x86_pkg_temp_thermal intel_powerclamp coretemp crc32_pclmul mgag200 ghash_clmulni_intel drm_kms_helper cec aesni_intel drm libaes crypto_simd cryptd glue_helper mei_me dell_smbios iTCO_wdt evdev intel_pmc_bxt iTCO_vendor_support dcdbas pcspkr rapl dell_wmi_descriptor wmi_bmof sg i2c_algo_bit watchdog mei acpi_ipmi ipmi_si button nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ipmi_devintf ipmi_msghandler ip_tables x_tables autofs4 ext4 crc16 mbcache jbd2 dm_mod raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor sd_mod t10_pi crc_t10dif crct10dif_generic raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod ahci libahci tg3 libata xhci_pci libphy xhci_hcd ptp usbcore crct10dif_pclmul crct10dif_common bnxt_en crc32c_intel scsi_mod [709732.358941] pps_core i2c_i801 lpc_ich i2c_smbus wmi usb_common [709732.358957] CPU: 3 PID: 456 Comm: jbd2/dm-0-8 Not tainted 5.10.0-0.bpo.5-amd64 #1 Debian 5.10.24-1~bpo10+1 [709732.358959] Hardware name: Dell Inc. PowerEdge R440/04JN2K, BIOS 2.9.3 09/23/2020 [709732.358964] RIP: 0010:kernel_fpu_begin_mask+0xae/0xe0 [709732.358969] Code: ae 54 24 04 83 e3 01 75 38 48 8b 44 24 08 65 48 33 04 25 28 00 00 00 75 33 48 83 c4 10 5b c3 65 8a 05 5e 21 5e 76 84 c0 74 92 <0f> 0b eb 8e f0 80 4f 01 40 48 81 c7 00 14 00 00 e8 dd fb ff ff eb [709732.358972] RSP: 0018:ffffbb9700304740 EFLAGS: 00010202 [709732.358976] RAX: 0000000000000001 RBX: 0000000000000003 RCX: 0000000000000001 [709732.358979] RDX: ffffbb9700304970 RSI: ffff922fe1952e00 RDI: 0000000000000003 [709732.358981] RBP: ffffbb9700304970 R08: ffff922fc868a600 R09: ffff922fc711e462 [709732.358984] R10: 000000000000005f R11: ffff922ff0b27180 R12: ffffbb9700304960 [709732.358987] R13: ffffbb9700304b08 R14: ffff922fc664b6c8 R15: ffff922fc664b660 [709732.358990] FS: 0000000000000000(0000) GS:ffff92371fec0000(0000) knlGS:0000000000000000 [709732.358993] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [709732.358996] CR2: 0000557a6655bdd0 CR3: 000000026020a001 CR4: 00000000007706e0 [709732.358999] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [709732.359001] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [709732.359003] PKRU: 55555554 [709732.359005] Call Trace: [709732.359009] [709732.359035] nft_pipapo_avx2_lookup+0x4c/0x1cba [nf_tables] [709732.359046] ? sched_clock+0x5/0x10 [709732.359054] ? sched_clock_cpu+0xc/0xb0 [709732.359061] ? record_times+0x16/0x80 [709732.359068] ? plist_add+0xc1/0x100 [709732.359073] ? psi_group_change+0x47/0x230 [709732.359079] ? skb_clone+0x4d/0xb0 [709732.359085] ? enqueue_task_rt+0x22b/0x310 [709732.359098] ? bnxt_start_xmit+0x1e8/0xaf0 [bnxt_en] [709732.359102] ? packet_rcv+0x40/0x4a0 [709732.359121] nft_lookup_eval+0x59/0x160 [nf_tables] [709732.359133] nft_do_chain+0x350/0x500 [nf_tables] [709732.359152] ? nft_lookup_eval+0x59/0x160 [nf_tables] [709732.359163] ? nft_do_chain+0x364/0x500 [nf_tables] [709732.359172] ? fib4_rule_action+0x6d/0x80 [709732.359178] ? fib_rules_lookup+0x107/0x250 [709732.359184] nft_nat_do_chain+0x8a/0xf2 [nft_chain_nat] [709732.359193] nf_nat_inet_fn+0xea/0x210 [nf_nat] [709732.359202] nf_nat_ipv4_out+0x14/0xa0 [nf_nat] [709732.359207] nf_hook_slow+0x44/0xc0 [709732.359214] ip_output+0xd2/0x100 [709732.359221] ? __ip_finish_output+0x210/0x210 [709732.359226] ip_forward+0x37d/0x4a0 [709732.359232] ? ip4_key_hashfn+0xb0/0xb0 [709732.359238] ip_subli ---truncated---

CVSS v3
5.5
EG Score
5.5MEDIUMmedium confidence
EG Risk
25
EG Risk 25/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity55% × 45%
Impact severity (EG Severity): CVSS 5.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.2% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.2%
EPSS %ILE
13th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.

EG Severity
5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-17). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

March 25, 2024

Last Modified

March 17, 2025

References (3)

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
linux—
  • every version up to 5.10.46-1: fixed in 5.10.46-1
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
linux—
  • every version up to 5.14.6-1: fixed in 5.14.6-1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
linux—
  • every version up to 5.14.6-1: fixed in 5.14.6-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux—
  • every version up to 5.14.6-1: fixed in 5.14.6-1
—

Data Freshness Timeline

(refreshed 8× in last 7d / 33× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 96 of 194 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 4 repeat rows among the latest 100 are merged into the row they repeat. The 98 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-23 16:28 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  2. 2026-10-22 16:29 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  3. 2026-10-21 16:28 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  4. 2026-10-20 16:28 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  5. 2026-10-19 16:28 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  6. 2026-10-18 16:28 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  7. 2026-10-18 08:49 UTCEG score recompute
  8. 2026-10-17 16:29 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  9. 2026-10-16 16:34 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  10. 2026-10-15 16:28 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  11. 2026-10-14 16:29 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  12. 2026-10-13 16:28 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  13. 2026-10-12 19:05 UTCEG score recompute
  14. 2026-10-12 16:30 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  15. 2026-10-11 23:31 UTCEG score recompute
  16. 2026-10-11 17:54 UTCOSV refresh
  17. 2026-10-11 13:44 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  18. 2026-10-10 19:56 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  19. 2026-10-09 20:04 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  20. 2026-10-08 16:40 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  21. 2026-10-07 23:45 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  22. 2026-10-06 15:14 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  23. 2026-10-05 17:40 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  24. 2026-10-04 23:19 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  25. 2026-10-03 14:22 UTCEPSS rescoreEPSS 0.2% · 12th percentile
Show 71 more
  1. 2026-10-02 16:23 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  2. 2026-09-30 15:45 UTCEG score recompute
  3. 2026-09-30 15:00 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  4. 2026-09-29 15:15 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  5. 2026-09-28 13:47 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  6. 2026-09-26 15:54 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  7. 2026-09-26 00:21 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  8. 2026-09-24 14:00 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  9. 2026-09-23 13:45 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  10. 2026-09-22 14:44 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  11. 2026-09-22 04:46 UTCOSV refresh
  12. 2026-09-21 20:28 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  13. 2026-09-20 20:13 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  14. 2026-09-19 15:38 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  15. 2026-09-18 19:24 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  16. 2026-09-17 19:23 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  17. 2026-09-16 14:05 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  18. 2026-09-15 03:06 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  19. 2026-09-12 14:57 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  20. 2026-09-11 14:49 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  21. 2026-09-11 09:33 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  22. 2026-09-08 21:57 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  23. 2026-09-07 15:58 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  24. 2026-09-06 13:45 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  25. 2026-09-05 15:25 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  26. 2026-09-04 13:57 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  27. 2026-09-04 05:03 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  28. 2026-09-03 02:29 UTCOSV refresh
  29. 2026-09-02 14:09 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  30. 2026-09-01 13:51 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  31. 2026-08-30 19:14 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  32. 2026-08-30 01:19 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  33. 2026-08-28 21:38 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  34. 2026-08-27 14:22 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  35. 2026-08-26 14:43 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  36. 2026-08-25 13:46 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  37. 2026-08-24 14:13 UTCEPSS rescoreEPSS 0.2% · 13th percentile
  38. 2026-08-21 23:46 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  39. 2026-08-20 22:52 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  40. 2026-08-19 17:01 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  41. 2026-08-18 13:45 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  42. 2026-08-17 13:44 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  43. 2026-08-16 15:14 UTCOSV refresh
  44. 2026-08-16 14:53 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  45. 2026-08-16 02:11 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  46. 2026-08-15 01:27 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  47. 2026-08-13 21:57 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  48. 2026-08-12 13:48 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  49. 2026-08-11 13:38 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  50. 2026-08-09 13:44 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  51. 2026-08-08 16:34 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  52. 2026-08-07 16:24 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  53. 2026-08-06 13:44 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  54. 2026-08-05 19:15 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  55. 2026-08-04 15:06 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  56. 2026-08-04 10:34 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  57. 2026-08-03 10:33 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  58. 2026-08-02 02:24 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  59. 2026-08-01 09:06 UTCOSV refresh
  60. 2026-08-01 04:13 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  61. 2026-07-30 16:25 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  62. 2026-07-30 01:28 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  63. 2026-07-28 15:33 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  64. 2026-07-26 14:52 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  65. 2026-07-25 14:15 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  66. 2026-07-24 14:15 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  67. 2026-07-23 14:16 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  68. 2026-07-23 02:06 UTCEG score recompute
  69. 2026-07-22 22:52 UTCEG score recompute
  70. 2026-07-22 14:06 UTCEPSS rescoreEPSS 0.2% · 14th percentile
  71. 2026-07-21 15:22 UTCEPSS rescoreEPSS 0.2% · 14th percentile

Frequently asked(5)

What is CVE-2021-47174?
CVE-2021-47174 is a medium-severity vulnerability; its CVE record was published on March 25, 2024. In the Linux kernel, the following vulnerability has been resolved: netfilter: nftsetpipapoavx2: Add irqfpu_usable() check, fallback to non-AVX2 version Arturo reported this backtrace: [709732.358791] WARNING: CPU: 3 PID: 456 at arch/x86/kernel/fpu/core.c:128 kernelfpubegin_mask+0xae/0xe0…
When was the CVE record for CVE-2021-47174 published?
The CVE record for CVE-2021-47174 was published on March 25, 2024. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of March 17, 2025; the record at its source may have been updated since.
Is CVE-2021-47174 actively exploited?
CVE-2021-47174 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (13th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2021-47174?
CVE-2021-47174 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2021-47174?
A fix for CVE-2021-47174 is available: update to the fixed version the vendor names in its advisory.

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