CVE-2021-3782

CRITICALNVD 6.69.8▲
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2022-09-25. NVD baseline CVSS 6.6; sources differ by 3.2.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
9.8EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.6Exploit: None knownExposed: 0

A fix is available — apply it.

An internal reference count is held on the buffer pool, incremented every time a new buffer is created from the pool. The reference count is maintained as an int; on LP64 systems this can cause the reference count to overflow if the client creates a large number of wl_shm buffer objects, or if it can coerce the server to create a large number of external references to the buffer storage. With the reference count overflowing, a use-after-free can be constructed on the wl_shm_pool tracking structure, where values may be incremented or decremented; it may also be possible to construct a limited oracle to leak 4 bytes of server-side memory to the attacking client at a time.

CVSS v3
6.6
EG Score
9.8(medium)
EG Risk
44(Track)
EG Risk 44/100SSVC: 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%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
23%
KEV
Not listed

Published

September 23, 2022

Last Modified

May 22, 2025

References (2)

Vendor Advisories for CVE-2021-3782(1)

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

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulibwayland-client0 (1.20.0-1ubuntu0.1) @ jammy2026-05-25ubuntu
ubuntulibwayland-client0 (1.12.0-1~ubuntu16.04.3+esm1) @ xenial2026-05-25ubuntu
redhatwayland-0:1.21.0-1.el82023-05-16redhat

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

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
wayland1.18.0-2~exp1.1 ... 1.26.0-1 (19 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
wayland—1.21.0-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
wayland—1.21.0-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
wayland—1.21.0-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(3)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 7× in last 7d / 31× 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 155 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2021-3782?
CVE-2021-3782 is a critical vulnerability published on September 23, 2022. An internal reference count is held on the buffer pool, incremented every time a new buffer is created from the pool. The reference count is maintained as an int; on LP64 systems this can cause the reference count to overflow if the client creates a large number of wlshm buffer objects, or if it…
When was CVE-2021-3782 disclosed?
CVE-2021-3782 was first published in the National Vulnerability Database on September 23, 2022, with the most recent update on May 22, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-3782 actively exploited?
CVE-2021-3782 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 77.0% of all scored CVEs.
What is the CVSS score of CVE-2021-3782?
CVE-2021-3782 has a CVSS v3 base score of 6.6 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.8.
How do I remediate CVE-2021-3782?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-3782, 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

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