CVE-2021-47169

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

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, ghsa, nvd
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: 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:

serial: rp2: use 'request_firmware' instead of 'request_firmware_nowait'

In 'rp2_probe', the driver registers 'rp2_uart_interrupt' then calls 'rp2_fw_cb' through 'request_firmware_nowait'. In 'rp2_fw_cb', if the firmware don't exists, function just return without initializing ports of 'rp2_card'. But now the interrupt handler function has been registered, and when an interrupt comes, 'rp2_uart_interrupt' may access those ports then causing NULL pointer dereference or other bugs.

Because the driver does some initialization work in 'rp2_fw_cb', in order to make the driver ready to handle interrupts, 'request_firmware' should be used instead of asynchronous 'request_firmware_nowait'.

This report reveals it:

INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef-dirty #45 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59- gc9ba5276e321-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xec/0x156 lib/dump_stack.c:118 assign_lock_key kernel/locking/lockdep.c:727 [inline] register_lock_class+0x14e5/0x1ba0 kernel/locking/lockdep.c:753 __lock_acquire+0x187/0x3750 kernel/locking/lockdep.c:3303 lock_acquire+0x124/0x340 kernel/locking/lockdep.c:3907 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x32/0x50 kernel/locking/spinlock.c:144 spin_lock include/linux/spinlock.h:329 [inline] rp2_ch_interrupt drivers/tty/serial/rp2.c:466 [inline] rp2_asic_interrupt.isra.9+0x15d/0x990 drivers/tty/serial/rp2.c:493 rp2_uart_interrupt+0x49/0xe0 drivers/tty/serial/rp2.c:504 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline] handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670 RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61 Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 c2 2f 8c 48 89 e5 e8 fb 31 e7 f8 8b 05 75 af 8d 03 85 c0 7e 07 0f 00 2d 8a 61 65 00 fb f4 <5d> c3 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde RAX: 0000000000000000 RBX: ffffffff8bde7e48 RCX: ffffffff88a21285 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2fc200 RBP: ffff88806b71fcc8 R08: fffffbfff185f840 R09: fffffbfff185f840 R10: 0000000000000001 R11: fffffbfff185f840 R12: 0000000000000002 R13: ffffffff8bea18a0 R14: 0000000000000000 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0x6f/0x360 arch/x86/kernel/process.c:557 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 PGD 8000000056d27067 P4D 8000000056d27067 PUD 56d28067 PMD 0 Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef-dirty #45 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59- gc9ba5276e321-prebuilt.qemu.org 04/01/2014 RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline] RIP: 0010:rp2_ch_interrupt drivers/tty/serial/rp2.c:472 [inline] RIP: 0010:rp2_asic_interrupt.isra.9+0x181/0x990 drivers/tty/serial/rp2.c: 493 Co ---truncated---

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
25(Track)
EG Risk 25/100SSVC: 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
Severity55% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
13%
KEV
Not listed

Published

March 25, 2024

Last Modified

March 3, 2025

References (16)

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 44× 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 105 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2021-47169?
CVE-2021-47169 is a medium vulnerability published on March 25, 2024. In the Linux kernel, the following vulnerability has been resolved: serial: rp2: use 'requestfirmware' instead of 'requestfirmware_nowait' In 'rp2probe', the driver registers 'rp2uart_interrupt' then calls 'rp2fwcb' through 'requestfirmwarenowait'. In 'rp2fwcb', if the firmware don't exists,…
When was CVE-2021-47169 disclosed?
CVE-2021-47169 was first published in the National Vulnerability Database on March 25, 2024, with the most recent update on March 3, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-47169 actively exploited?
CVE-2021-47169 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 86.5% of all scored CVEs.
What is the CVSS score of CVE-2021-47169?
CVE-2021-47169 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2021-47169?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-47169, 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-2021-47169

Explore →

Is Your Infrastructure Affected by CVE-2021-47169?

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

Start Free Scan →Browse All CVEs