CVE-2021-26701

HIGHPre-NVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.1 under the CNA's CVSS (NVD's own analysis pending). EPSS exploit probability: 30.3%, top 2% 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: cna:microsoft, epss
Trending — 3 sources updated this weekElevated
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 30%CVSS: 8.1Exploit: NoneExposed: 0

A fix is available — apply it.

.NET Core Remote Code Execution Vulnerability

CVSS v3
8.1
EG Score
8.1(medium)
EG Risk
52(Track)
EG Risk 52/100SSVC: 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
Severity81% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
98.0%
KEV
Not listed

Published

February 25, 2021

Last Modified

May 28, 2026

Advisory Details (7)

Auto-updated May 28, 2026
Patch available. Sources: microsoft.
generic

[SECURITY] Fedora 32 Update: dotnet3.1-3.1.113-1.fc32 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S2AZOUKMCHT2WBHR7MYDTYXWOBHZW5P5/
generic

[SECURITY] Fedora 33 Update: dotnet3.1-3.1.113-1.fc33 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UBOSSX7U6BSHV5RI74FCOW4ITJ5RRJR5/
generic

[SECURITY] Fedora 32 Update: dotnet5.0-5.0.104-1.fc32 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YLFATXASXW4OV2ZBSRP4G55HJH73QPBP/
generic

[SECURITY] Fedora 33 Update: dotnet5.0-5.0.104-1.fc33 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WA5WQJVHUL5C4XMJTLY3C67R4WP35EF4/
generic

[SECURITY] Fedora 34 Update: dotnet5.0-5.0.104-1.fc34 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TW3ZSJTTMZAFKGW7NJWTVVFZUYYU2SJZ/
generic

[SECURITY] Fedora 34 Update: dotnet3.1-3.1.113-1.fc34 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XPUKFHIGP5YNJRRFWKDJ2XRS4WTFJNNK/
microsoft Patch Available

Security Update Guide - Microsoft Security Response Center

Security Update Guide - Microsoft Security Response Center. Patch available via Microsoft Security Update

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26701

Patch Availability(6)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatrh-dotnet21-dotnet-0:2.1.522-1.el7_92021-03-09redhat
redhatrh-dotnet31-dotnet-0:3.1.113-1.el7_92021-03-09redhat
redhatrh-dotnet50-dotnet-0:5.0.104-1.el7_92021-03-09redhat
redhatdotnet-0:2.1.522-1.el8_32021-03-09redhat
redhatdotnet3.1-0:3.1.113-1.el8_32021-03-09redhat
redhatdotnet5.0-0:5.0.104-1.el8_32021-03-09redhat

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)
NuGet(1)
PackageVulnerable rangeFixed inDependents
System.Text.Encodings.Web5.0.05.0.1—

All Vendor Advisories

(7)

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

Related CVEs(same vendor)

Frequently asked(5)

What is CVE-2021-26701?
CVE-2021-26701 is a high vulnerability published on February 25, 2021. .NET Core Remote Code Execution Vulnerability
When was CVE-2021-26701 disclosed?
CVE-2021-26701 was first published in the National Vulnerability Database on February 25, 2021, with the most recent update on May 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-26701 actively exploited?
CVE-2021-26701 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 98.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-26701?
CVE-2021-26701 has a CVSS v4.0 base score of 8.1 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2021-26701?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-26701, 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-2021-26701

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