CVE-2021-47274

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2024-05-21. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 3 sources updated this week
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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

tracing: Correct the length check which causes memory corruption

We've suffered from severe kernel crashes due to memory corruption on our production environment, like,

Call Trace: [1640542.554277] general protection fault: 0000 [#1] SMP PTI [1640542.554856] CPU: 17 PID: 26996 Comm: python Kdump: loaded Tainted:G [1640542.556629] RIP: 0010:kmem_cache_alloc+0x90/0x190 [1640542.559074] RSP: 0018:ffffb16faa597df8 EFLAGS: 00010286 [1640542.559587] RAX: 0000000000000000 RBX: 0000000000400200 RCX: 0000000006e931bf [1640542.560323] RDX: 0000000006e931be RSI: 0000000000400200 RDI: ffff9a45ff004300 [1640542.560996] RBP: 0000000000400200 R08: 0000000000023420 R09: 0000000000000000 [1640542.561670] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff9a20608d [1640542.562366] R13: ffff9a45ff004300 R14: ffff9a45ff004300 R15: 696c662f65636976 [1640542.563128] FS: 00007f45d7c6f740(0000) GS:ffff9a45ff840000(0000) knlGS:0000000000000000 [1640542.563937] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1640542.564557] CR2: 00007f45d71311a0 CR3: 000000189d63e004 CR4: 00000000003606e0 [1640542.565279] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [1640542.566069] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [1640542.566742] Call Trace: [1640542.567009] anon_vma_clone+0x5d/0x170 [1640542.567417] __split_vma+0x91/0x1a0 [1640542.567777] do_munmap+0x2c6/0x320 [1640542.568128] vm_munmap+0x54/0x70 [1640542.569990] __x64_sys_munmap+0x22/0x30 [1640542.572005] do_syscall_64+0x5b/0x1b0 [1640542.573724] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [1640542.575642] RIP: 0033:0x7f45d6e61e27

James Wang has reproduced it stably on the latest 4.19 LTS. After some debugging, we finally proved that it's due to ftrace buffer out-of-bound access using a debug tool as follows: [ 86.775200] BUG: Out-of-bounds write at addr 0xffff88aefe8b7000 [ 86.780806] no_context+0xdf/0x3c0 [ 86.784327] __do_page_fault+0x252/0x470 [ 86.788367] do_page_fault+0x32/0x140 [ 86.792145] page_fault+0x1e/0x30 [ 86.795576] strncpy_from_unsafe+0x66/0xb0 [ 86.799789] fetch_memory_string+0x25/0x40 [ 86.804002] fetch_deref_string+0x51/0x60 [ 86.808134] kprobe_trace_func+0x32d/0x3a0 [ 86.812347] kprobe_dispatcher+0x45/0x50 [ 86.816385] kprobe_ftrace_handler+0x90/0xf0 [ 86.820779] ftrace_ops_assist_func+0xa1/0x140 [ 86.825340] 0xffffffffc00750bf [ 86.828603] do_sys_open+0x5/0x1f0 [ 86.832124] do_syscall_64+0x5b/0x1b0 [ 86.835900] entry_SYSCALL_64_after_hwframe+0x44/0xa9

commit b220c049d519 ("tracing: Check length before giving out the filter buffer") adds length check to protect trace data overflow introduced in 0fc1b09ff1ff, seems that this fix can't prevent overflow entirely, the length check should also take the sizeof entry->array[0] into account, since this array[0] is filled the length of trace data and occupy addtional space and risk overflow.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
59(Track)
EG Risk 59/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
51%
KEV
Not listed

Published

May 21, 2024

Last Modified

August 5, 2026

Advisory Details (7)

Auto-updated Aug 5, 2026
No patch confirmed yet.
generic

tracing: Correct the length check which causes memory corruption - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/3e08a9f9760f4a70d633c328a76408e62d6f80a3
generic

tracing: Correct the length check which causes memory corruption - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b16a249eca2230c2cd66fa1d4b94743bd9b6ef92
generic

tracing: Correct the length check which causes memory corruption - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/43c32c22254b9328d7abb1c2b0f689dc67838e60
generic

tracing: Correct the length check which causes memory corruption - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d63f00ec908b3be635ead5d6029cc94246e1f38d
generic

tracing: Correct the length check which causes memory corruption - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/31ceae385556c37e4d286cb6378696448f566883
generic

tracing: Correct the length check which causes memory corruption - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2d598902799886d67947406f26ee8e5fd2ca097f
generic

tracing: Correct the length check which causes memory corruption - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/edcce01e0e50840a9aa6a70baed21477bdd2c9f9

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 13× in last 7d / 45× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

Showing the most recent 100 of 124 total refreshes for this CVE.

  1. 2026-08-07 16:24 UTCEPSS rescore
  2. 2026-08-06 13:44 UTCEPSS rescore
  3. 2026-08-05 19:15 UTCEPSS rescore
  4. 2026-08-05 09:41 UTCEG score recompute
  5. 2026-08-05 09:40 UTCGHSA enrichment
  6. 2026-08-04 15:06 UTCEPSS rescore
  7. 2026-08-04 12:12 UTCEG score recompute
  8. 2026-08-04 12:12 UTCGHSA enrichment
  9. 2026-08-04 10:34 UTCEPSS rescore
  10. 2026-08-04 09:52 UTCEG score recompute
  11. 2026-08-04 09:52 UTCGHSA enrichment
  12. 2026-08-03 10:33 UTCEPSS rescore
  13. 2026-08-02 02:24 UTCEPSS rescore
  14. 2026-08-01 04:13 UTCEPSS rescore
  15. 2026-08-01 02:42 UTCOSV refresh
  16. 2026-07-30 16:25 UTCEPSS rescore
  17. 2026-07-30 01:28 UTCEPSS rescore
  18. 2026-07-28 15:33 UTCEPSS rescore
  19. 2026-07-26 14:52 UTCEPSS rescore
  20. 2026-07-25 14:15 UTCEPSS rescore
  21. 2026-07-24 14:15 UTCEPSS rescore
  22. 2026-07-24 14:15 UTCEPSS rescore
  23. 2026-07-23 14:16 UTCEPSS rescore
  24. 2026-07-23 02:06 UTCEG score recompute
  25. 2026-07-22 22:53 UTCEG score recompute
Show 75 more
  1. 2026-07-22 14:06 UTCEPSS rescore
  2. 2026-07-21 15:22 UTCEPSS rescore
  3. 2026-07-21 15:22 UTCEPSS rescore
  4. 2026-07-20 17:05 UTCEPSS rescore
  5. 2026-07-19 02:27 UTCEPSS rescore
  6. 2026-07-19 02:27 UTCEPSS rescore
  7. 2026-07-18 10:02 UTCEPSS rescore
  8. 2026-07-16 17:00 UTCEPSS rescore
  9. 2026-07-16 17:00 UTCEPSS rescore
  10. 2026-07-15 16:55 UTCEPSS rescore
  11. 2026-07-15 01:58 UTCEPSS rescore
  12. 2026-07-15 01:58 UTCEPSS rescore
  13. 2026-07-14 09:55 UTCOSV refresh
  14. 2026-07-13 22:27 UTCEPSS rescore
  15. 2026-07-13 06:11 UTCEPSS rescore
  16. 2026-07-13 06:11 UTCEPSS rescore
  17. 2026-07-12 05:44 UTCEPSS rescore
  18. 2026-07-11 08:25 UTCEPSS rescore
  19. 2026-07-09 19:07 UTCEPSS rescore
  20. 2026-07-09 19:07 UTCEPSS rescore
  21. 2026-07-08 15:12 UTCEPSS rescore
  22. 2026-07-08 15:12 UTCEPSS rescore
  23. 2026-07-07 13:43 UTCEPSS rescore
  24. 2026-07-06 16:25 UTCEPSS rescore
  25. 2026-07-06 16:25 UTCEPSS rescore
  26. 2026-07-06 02:21 UTCEPSS rescore
  27. 2026-07-06 02:21 UTCEPSS rescore
  28. 2026-07-05 02:28 UTCEPSS rescore
  29. 2026-07-05 02:28 UTCEPSS rescore
  30. 2026-07-04 06:29 UTCEPSS rescore
  31. 2026-07-04 06:29 UTCEPSS rescore
  32. 2026-07-01 15:04 UTCEPSS rescore
  33. 2026-06-30 23:20 UTCEPSS rescore
  34. 2026-06-29 14:04 UTCEPSS rescore
  35. 2026-06-29 14:04 UTCEPSS rescore
  36. 2026-06-28 14:05 UTCEPSS rescore
  37. 2026-06-28 04:54 UTCEPSS rescore
  38. 2026-06-28 04:54 UTCEPSS rescore
  39. 2026-06-27 03:07 UTCEPSS rescore
  40. 2026-06-27 03:06 UTCEPSS rescore
  41. 2026-06-26 10:37 UTCOSV refresh
  42. 2026-06-25 13:48 UTCEPSS rescore
  43. 2026-06-25 13:48 UTCEPSS rescore
  44. 2026-06-24 14:03 UTCEPSS rescore
  45. 2026-06-24 14:03 UTCEPSS rescore
  46. 2026-06-23 21:31 UTCEPSS rescore
  47. 2026-06-23 21:31 UTCEPSS rescore
  48. 2026-06-22 14:24 UTCEPSS rescore
  49. 2026-06-21 14:55 UTCEPSS rescore
  50. 2026-06-21 01:58 UTCEPSS rescore
  51. 2026-06-21 01:58 UTCEPSS rescore
  52. 2026-06-19 19:24 UTCEPSS rescore
  53. 2026-06-19 19:24 UTCEPSS rescore
  54. 2026-06-18 17:51 UTCEPSS rescore
  55. 2026-06-18 17:51 UTCEPSS rescore
  56. 2026-06-17 17:51 UTCEPSS rescore
  57. 2026-06-17 17:51 UTCEPSS rescore
  58. 2026-06-16 17:51 UTCEPSS rescore
  59. 2026-06-15 17:46 UTCEPSS rescore
  60. 2026-06-14 23:15 UTCEPSS rescore
  61. 2026-06-14 23:15 UTCEPSS rescore
  62. 2026-06-13 22:58 UTCEPSS rescore
  63. 2026-06-13 22:58 UTCEPSS rescore
  64. 2026-06-12 23:10 UTCEPSS rescore
  65. 2026-06-11 13:58 UTCEPSS rescore
  66. 2026-06-10 22:16 UTCEPSS rescore
  67. 2026-06-10 13:20 UTCEPSS rescore
  68. 2026-06-08 17:11 UTCOSV refresh
  69. 2026-06-08 14:15 UTCEPSS rescore
  70. 2026-06-08 14:15 UTCEPSS rescore
  71. 2026-06-08 14:15 UTCEPSS rescore
  72. 2026-06-07 15:23 UTCEPSS rescore
  73. 2026-06-07 15:23 UTCEPSS rescore
  74. 2026-06-06 13:46 UTCEPSS rescore
  75. 2026-06-06 13:46 UTCEPSS rescore

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2021-47274?
CVE-2021-47274 is a critical vulnerability published on May 21, 2024. In the Linux kernel, the following vulnerability has been resolved: tracing: Correct the length check which causes memory corruption We've suffered from severe kernel crashes due to memory corruption on our production environment, like, Call Trace: [1640542.554277] general protection fault: 0000…
When was CVE-2021-47274 disclosed?
CVE-2021-47274 was first published in the National Vulnerability Database on May 21, 2024, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-47274 actively exploited?
CVE-2021-47274 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 48.6% of all scored CVEs.
What is the CVSS score of CVE-2021-47274?
CVE-2021-47274 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2021-47274?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-47274, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2021-47274

Explore →

Is Your Infrastructure Affected by CVE-2021-47274?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs