CVE-2021-3506

HIGHNVD 7.17.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.1 under NVD CVSS v3. EPSS exploit probability: 0.4%, top 70% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
7.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.1Exploit: None knownExposed: 0

A fix is available — apply it.

An out-of-bounds (OOB) memory access flaw was found in fs/f2fs/node.c in the f2fs module in the Linux kernel in versions before 5.12.0-rc4. A bounds check failure allows a local attacker to gain access to out-of-bounds memory leading to a system crash or a leak of internal kernel information. The highest threat from this vulnerability is to system availability.

CVSS v3
7.1
EG Score
7.1(medium)
EG Risk
37(Track)
EG Risk 37/100SSVC: 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
Severity71% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
28%
KEV
Not listed

Published

April 19, 2021

Last Modified

September 1, 2026

Advisory Details (6)

Auto-updated Sep 1, 2026
Patch available. Sources: redhat.
generic

NetApp Product Security

https://security.netapp.com/advisory/ntap-20210611-0007/
generic Patch Available

[SECURITY] [DLA 2690-1] linux-4.19 security update

https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
redhat Patch Available

1944298 – (CVE-2021-3506) CVE-2021-3506 kernel: Out of bounds memory access bug in get_next_net_page() in fs/f2fs/node.c

https://bugzilla.redhat.com/show_bug.cgi?id=1944298
generic

oss-security - Re: Linux kernel: f2fs: out-of-bounds memory access bug

http://www.openwall.com/lists/oss-security/2021/05/08/1
generic

oss-security - Linux kernel: f2fs: out-of-bounds memory access bug

https://www.openwall.com/lists/oss-security/2021/03/28/2
generic

[PATCH] f2fs: fix to avoid out-of-bounds memory access

https://www.mail-archive.com/linux-kernel%40vger.kernel.org/msg2520013.html

Vendor Advisories for CVE-2021-3506(1)

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

Patch Availability(8)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-modules-5.4.0-1041-kvm (5.4.0-1041.42) @ focal2026-05-26ubuntu
ubuntulinux-image-lowlatency (5.11.0.22.23) @ hirsute2026-05-26ubuntu
ubuntulinux-image-raspi2-hwe-18.04 (5.4.0.1038.73) @ focal2026-05-26ubuntu
ubuntulinux-image-unsigned-5.11.0-1009-kvm (5.11.0-1009.9) @ hirsute2026-05-26ubuntu
ubuntulinux-image-oem-20.04-edge (5.10.0.1033.34) @ focal2026-05-26ubuntu
ubuntukernel-image-5.8.0-63-generic-lpae-di (5.8.0-63.71) @ groovy2026-05-26ubuntu
ubuntulinux-tools-aws-hwe (4.15.0.1124.114) @ xenial2026-05-26ubuntu
ubuntulinux-image-lowlatency (4.4.0.222.229) @ xenial2026-05-26ubuntu

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.

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux—5.10.38-1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux—5.10.38-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux—5.10.38-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux—5.10.38-1—
Debian:9(1)
PackageVulnerable rangeFixed inDependents
linux-4.194.19.132-1~deb9u1 ... 4.19.181-1~deb9u1 (7 versions)4.19.194-1~deb9u1—

Weakness Classification(1)

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

All Vendor Advisories

(9)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 9× in last 7d / 33× 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 175 total refreshes for this CVE.

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

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2021-3506?
CVE-2021-3506 is a high vulnerability published on April 19, 2021. An out-of-bounds (OOB) memory access flaw was found in fs/f2fs/node.c in the f2fs module in the Linux kernel in versions before 5.12.0-rc4. A bounds check failure allows a local attacker to gain access to out-of-bounds memory leading to a system crash or a leak of internal kernel information. The…
When was CVE-2021-3506 disclosed?
CVE-2021-3506 was first published in the National Vulnerability Database on April 19, 2021, with the most recent update on September 1, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-3506 actively exploited?
CVE-2021-3506 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 72.3% of all scored CVEs.
What is the CVSS score of CVE-2021-3506?
CVE-2021-3506 has a CVSS v3 base score of 7.1 (NVD).
How do I remediate CVE-2021-3506?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-3506, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-3506

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