CVE-2021-1615

HIGHNVD 8.68.6—
EchelonGraph scoreMEDIUM confidence

Score 8.6 from GitHub Security Advisory (severity: HIGH) published 2022-05-24. NVD baseline CVSS 8.6; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
8.6EG
EchelonGraph verdictPlan mitigationRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1.3%CVSS: 8.6Exploit: None knownExposed services: Not assessed

A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).

A vulnerability in the packet processing functionality of Cisco Embedded Wireless Controller (EWC) Software for Catalyst Access Points (APs) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected AP. This vulnerability is due to insufficient buffer allocation. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to exhaust available resources and cause a DoS condition on an affected AP, as well as a DoS condition for client traffic traversing the AP.

CVSS v3
8.6
EG Score
8.6HIGHmedium confidence
EG Risk
54
EG Risk 54/100

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 (value × EchelonGraph’s weight)
Severity86% × 45%
The EG Score, 8.6 of 10.
Exploitation1% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it and apply that within your standard update timelines at low or medium mission impact and sooner than that at high; until then, restrict network exposure of the affected system or apply the vendor's mitigation.
EPSS PROB
1.3%
EPSS %ILE
70th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it and apply that within your standard update timelines at low or medium mission impact and sooner than that at high; until then, restrict network exposure of the affected system or apply the vendor's mitigation.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

Published

September 23, 2021

Last Modified

November 21, 2024

Advisory Details (1)

Auto-updated Sep 1, 2026
Fix referenced — no release confirmed yet.
generic

Cisco Embedded Wireless Controller Software for Catalyst Access Points Denial of Service Vulnerability

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-ewc-dos-g6JruHRT

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 28× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 89 of 167 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 11 repeat rows among the latest 100 are merged into the row they repeat. The 78 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-11 13:43 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  2. 2026-10-10 19:56 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  3. 2026-10-09 20:04 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  4. 2026-10-08 16:39 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  5. 2026-10-07 23:44 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  6. 2026-10-06 15:13 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  7. 2026-10-05 17:40 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  8. 2026-10-04 23:18 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  9. 2026-10-03 14:22 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  10. 2026-10-02 16:22 UTCEPSS rescoreEPSS 1.3% · 70th percentile
  11. 2026-10-01 19:46 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  12. 2026-09-30 15:27 UTCEG score recompute
  13. 2026-09-30 15:00 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  14. 2026-09-28 13:47 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  15. 2026-09-27 13:41 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  16. 2026-09-26 15:54 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  17. 2026-09-26 00:21 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  18. 2026-09-24 14:00 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  19. 2026-09-23 13:44 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  20. 2026-09-22 14:44 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  21. 2026-09-21 20:28 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  22. 2026-09-19 15:37 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  23. 2026-09-18 19:23 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  24. 2026-09-17 19:23 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  25. 2026-09-16 14:04 UTCEPSS rescoreEPSS 1.3% · 69th percentile
Show 64 more
  1. 2026-09-15 03:06 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  2. 2026-09-13 16:43 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  3. 2026-09-12 14:57 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  4. 2026-09-11 09:33 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  5. 2026-09-10 09:29 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  6. 2026-09-08 21:56 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  7. 2026-09-07 15:58 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  8. 2026-09-06 13:44 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  9. 2026-09-05 15:25 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  10. 2026-09-04 13:57 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  11. 2026-09-04 05:03 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  12. 2026-09-02 14:08 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  13. 2026-09-01 13:50 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  14. 2026-09-01 03:32 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  15. 2026-08-30 19:14 UTCEPSS rescoreEPSS 1.3% · 69th percentile
  16. 2026-08-30 01:19 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  17. 2026-08-28 21:37 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  18. 2026-08-27 14:22 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  19. 2026-08-26 14:42 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  20. 2026-08-25 13:45 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  21. 2026-08-23 00:16 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  22. 2026-08-21 23:46 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  23. 2026-08-20 22:52 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  24. 2026-08-19 17:01 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  25. 2026-08-18 13:45 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  26. 2026-08-17 13:43 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  27. 2026-08-16 14:52 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  28. 2026-08-16 02:11 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  29. 2026-08-15 01:27 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  30. 2026-08-13 21:57 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  31. 2026-08-12 13:47 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  32. 2026-08-11 13:38 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  33. 2026-08-09 13:43 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  34. 2026-08-08 16:33 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  35. 2026-08-07 16:23 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  36. 2026-08-06 13:43 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  37. 2026-08-05 19:14 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  38. 2026-08-04 15:06 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  39. 2026-08-04 10:34 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  40. 2026-08-03 10:32 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  41. 2026-08-02 02:24 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  42. 2026-08-01 04:12 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  43. 2026-07-30 16:25 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  44. 2026-07-30 01:27 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  45. 2026-07-26 14:52 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  46. 2026-07-25 14:15 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  47. 2026-07-24 14:15 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  48. 2026-07-23 14:15 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  49. 2026-07-23 01:56 UTCEG score recompute
  50. 2026-07-22 22:42 UTCEG score recompute
  51. 2026-07-22 14:05 UTCEPSS rescoreEPSS 1.3% · 68th percentile
  52. 2026-07-21 15:22 UTCEPSS rescoreEPSS 1.3% · 67th percentile
  53. 2026-07-20 17:04 UTCEPSS rescoreEPSS 1.3% · 67th percentile
  54. 2026-07-19 02:26 UTCEPSS rescoreEPSS 1.3% · 67th percentile
  55. 2026-07-18 10:02 UTCEPSS rescoreEPSS 1.3% · 67th percentile
  56. 2026-07-16 17:00 UTCEPSS rescoreEPSS 1.3% · 66th percentile
  57. 2026-07-15 16:55 UTCEPSS rescoreEPSS 1.3% · 66th percentile
  58. 2026-07-15 01:57 UTCEPSS rescoreEPSS 1.3% · 66th percentile
  59. 2026-07-13 22:27 UTCEPSS rescoreEPSS 1.3% · 66th percentile
  60. 2026-07-13 06:10 UTCEPSS rescoreEPSS 1.3% · 66th percentile
  61. 2026-07-12 05:44 UTCEPSS rescoreEPSS 1.3% · 66th percentile
  62. 2026-07-11 08:25 UTCEPSS rescoreEPSS 1.3% · 66th percentile
  63. 2026-07-09 19:07 UTCEPSS rescoreEPSS 1.3% · 66th percentile
  64. 2026-07-08 15:12 UTCEPSS rescoreEPSS 1.3% · 66th percentile

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2021-1615?
CVE-2021-1615 is a high-severity vulnerability; its CVE record was published on September 23, 2021. A vulnerability in the packet processing functionality of Cisco Embedded Wireless Controller (EWC) Software for Catalyst Access Points (APs) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected AP. This vulnerability is due to insufficient…
When was the CVE record for CVE-2021-1615 published?
The CVE record for CVE-2021-1615 was published on September 23, 2021. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of November 21, 2024; the record at its source may have been updated since.
Is CVE-2021-1615 actively exploited?
CVE-2021-1615 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.3% probability of exploitation in the next 30 days (70th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2021-1615?
CVE-2021-1615 has a CVSS v3 base score of 8.6 (NVD).
How do I remediate CVE-2021-1615?
A fix for CVE-2021-1615 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2021-1615

Explore →

Is Your Infrastructure Affected by CVE-2021-1615?

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

Book a Demo →Browse All CVEs