CVE-2021-36221

MEDIUMNVD 5.95.9—
EchelonGraph scoreMEDIUM confidence

Score 5.9 from GitHub Security Advisory published 2022-05-24. NVD baseline CVSS 5.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, nvd
5.9
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 3%CVSS: 5.9Exploit: NoneExposed: 0

A fix is available — apply it.

Go before 1.15.15 and 1.16.x before 1.16.7 has a race condition that can lead to a net/http/httputil ReverseProxy panic upon an ErrAbortHandler abort.

CVSS v3
5.9
EG Score
5.9(medium)
EPSS
86.4%
KEV
Not listed

Published

August 8, 2021

Last Modified

November 21, 2024

References (24)

Vendor Advisories for CVE-2021-36221(9)

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

Patch Availability(13)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatcontainer-tools:rhel8-8070020220929222448.390774192022-11-08redhat
redhatcontainer-native-virtualization/virt-cdi-uploadserver:v4.9.4-72022-04-26redhat
redhatrhmtc/openshift-velero-plugin-rhel8:v1.5.4-82022-04-19redhat
redhatodf4/volume-replication-rhel8-operator:v4.10.0-112022-04-13redhat
redhatmcg-0:5.10.0-72.el82022-04-13redhat
redhatservicemesh-prometheus-0:2.14.0-16.el8.12022-04-07redhat
redhatopenshift4-wincw/windows-machine-config-rhel8-operator:5.0.0-52022-03-28redhat
redhatopenshift-sandboxed-containers/osc-rhel8-operator:1.2.0-142022-03-14redhat
redhatopenshift-clients-0:4.9.0-202202140924.p0.g340e212.assembly.stream.el72022-02-23redhat
redhatopenshift4/ovirt-csi-driver-rhel8-operator:v4.9.0-202202120107.p0.g9302429.assembly.stream2022-02-23redhat
redhatopenshift-serverless-1/svls-must-gather-rhel8:1.19.0-12021-11-23redhat
redhatopenshift-serverless-clients-0:0.25.1-1.el82021-11-23redhat
redhatgo-toolset:rhel8-8050020210817155413.8aa623692021-11-09redhat

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.

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFixed inDependents
stdlib—1.16.7—

Weakness Classification(1)

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

Additional Vendor Advisories

(8)

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 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.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2021-36221?
CVE-2021-36221 is a medium vulnerability published on August 8, 2021. Go before 1.15.15 and 1.16.x before 1.16.7 has a race condition that can lead to a net/http/httputil ReverseProxy panic upon an ErrAbortHandler abort.
When was CVE-2021-36221 disclosed?
CVE-2021-36221 was first published in the National Vulnerability Database on August 8, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-36221 actively exploited?
CVE-2021-36221 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 86.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-36221?
CVE-2021-36221 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2021-36221?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-36221, 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.

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