CVE-2023-53021

HIGHNVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2025-03-27. NVD baseline CVSS 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
7.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.8Exploit: NoneExposed: 0

A fix is available — apply it.

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

net/sched: sch_taprio: fix possible use-after-free

syzbot reported a nasty crash [1] in net_tx_action() which made little sense until we got a repro.

This repro installs a taprio qdisc, but providing an invalid TCA_RATE attribute.

qdisc_create() has to destroy the just initialized taprio qdisc, and taprio_destroy() is called.

However, the hrtimer used by taprio had already fired, therefore advance_sched() called __netif_schedule().

Then net_tx_action was trying to use a destroyed qdisc.

We can not undo the __netif_schedule(), so we must wait until one cpu serviced the qdisc before we can proceed.

Many thanks to Alexander Potapenko for his help.

[1] BUG: KMSAN: uninit-value in queued_spin_trylock include/asm-generic/qspinlock.h:94 [inline] BUG: KMSAN: uninit-value in do_raw_spin_trylock include/linux/spinlock.h:191 [inline] BUG: KMSAN: uninit-value in __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline] BUG: KMSAN: uninit-value in _raw_spin_trylock+0x92/0xa0 kernel/locking/spinlock.c:138 queued_spin_trylock include/asm-generic/qspinlock.h:94 [inline] do_raw_spin_trylock include/linux/spinlock.h:191 [inline] __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline] _raw_spin_trylock+0x92/0xa0 kernel/locking/spinlock.c:138 spin_trylock include/linux/spinlock.h:359 [inline] qdisc_run_begin include/net/sch_generic.h:187 [inline] qdisc_run+0xee/0x540 include/net/pkt_sched.h:125 net_tx_action+0x77c/0x9a0 net/core/dev.c:5086 __do_softirq+0x1cc/0x7fb kernel/softirq.c:571 run_ksoftirqd+0x2c/0x50 kernel/softirq.c:934 smpboot_thread_fn+0x554/0x9f0 kernel/smpboot.c:164 kthread+0x31b/0x430 kernel/kthread.c:376 ret_from_fork+0x1f/0x30

Uninit was created at: slab_post_alloc_hook mm/slab.h:732 [inline] slab_alloc_node mm/slub.c:3258 [inline] __kmalloc_node_track_caller+0x814/0x1250 mm/slub.c:4970 kmalloc_reserve net/core/skbuff.c:358 [inline] __alloc_skb+0x346/0xcf0 net/core/skbuff.c:430 alloc_skb include/linux/skbuff.h:1257 [inline] nlmsg_new include/net/netlink.h:953 [inline] netlink_ack+0x5f3/0x12b0 net/netlink/af_netlink.c:2436 netlink_rcv_skb+0x55d/0x6c0 net/netlink/af_netlink.c:2507 rtnetlink_rcv+0x30/0x40 net/core/rtnetlink.c:6108 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536 __sys_sendmsg net/socket.c:2565 [inline] __do_sys_sendmsg net/socket.c:2574 [inline] __se_sys_sendmsg net/socket.c:2572 [inline] __x64_sys_sendmsg+0x367/0x540 net/socket.c:2572 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 6.0.0-rc2-syzkaller-47461-gac3859c02d7f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
35(Track)
EG Risk 35/100SSVC: 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
Severity78% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
7.8%
KEV
Not listed

Published

March 27, 2025

Last Modified

April 1, 2025

References (5)

Vendor Advisories for CVE-2023-53021(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatkernel-0:4.18.0-513.5.1.el8_92023-11-14redhat
redhatkernel-0:5.14.0-284.11.1.el9_22023-05-09redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 13× in last 7d / 47× 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.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2023-53021?
CVE-2023-53021 is a high vulnerability published on March 27, 2025. In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_taprio: fix possible use-after-free syzbot reported a nasty crash [1] in nettxaction() which made little sense until we got a repro. This repro installs a taprio qdisc, but providing an invalid TCA_RATE attribute.…
When was CVE-2023-53021 disclosed?
CVE-2023-53021 was first published in the National Vulnerability Database on March 27, 2025, with the most recent update on April 1, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2023-53021 actively exploited?
CVE-2023-53021 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 7.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2023-53021?
CVE-2023-53021 has a CVSS v3 base score of 7.8 (NVD).
How do I remediate CVE-2023-53021?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-53021, 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-2023-53021

Explore →

Is Your Infrastructure Affected by CVE-2023-53021?

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

Start Free Scan →Browse All CVEs