CVE-2021-45420

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2022-02-15. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
9.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 18%CVSS: 9.8Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Emerson Dixell XWEB-500 products are affected by arbitrary file write vulnerability in /cgi-bin/logo_extra_upload.cgi, /cgi-bin/cal_save.cgi, and /cgi-bin/lo_utils.cgi. An attacker will be able to write any file on the target system without any kind of authentication mechanism, and this can lead to denial of service and potentially remote code execution. Note: the product has not been supported since 2018 and should be removed or replaced.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
65(Track*)
EG Risk 65/100SSVC: 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%
Exploitation40% × 40%
Automatability30% × 15%
Action: Watch closely — could escalate to Attend.
EPSS
96.8%
KEV
Not listed

Published

February 14, 2022

Last Modified

July 9, 2026

Advisory Details (2)

Auto-updated Jul 19, 2026
No patch confirmed yet.
generic

Corporate

http://emerson.com
generic

Dixell

http://dixell.com

Weakness Classification(4)

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

Data Freshness Timeline

(refreshed 12× in last 7d / 50× 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. 2026-07-24 14:15 UTCEPSS rescore
  2. 2026-07-23 14:16 UTCEPSS rescore
  3. 2026-07-23 02:05 UTCEG score recompute
  4. 2026-07-22 22:52 UTCEG score recompute
  5. 2026-07-22 14:06 UTCEPSS rescore
  6. 2026-07-21 15:22 UTCEPSS rescore
  7. 2026-07-21 15:22 UTCEPSS rescore
  8. 2026-07-20 17:05 UTCEPSS rescore
  9. 2026-07-19 14:29 UTCEPSS rescore
  10. 2026-07-19 02:27 UTCEPSS rescore
  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. 2026-07-16 17:00 UTCEPSS rescore
  15. 2026-07-15 16:55 UTCEPSS rescore
  16. 2026-07-15 16:55 UTCEPSS rescore
  17. 2026-07-15 01:58 UTCEPSS rescore
  18. 2026-07-13 22:27 UTCEPSS rescore
  19. 2026-07-13 22:27 UTCEPSS rescore
  20. 2026-07-13 06:11 UTCEPSS rescore
  21. 2026-07-13 06:11 UTCEPSS rescore
  22. 2026-07-12 05:44 UTCEPSS rescore
  23. 2026-07-11 08:25 UTCEPSS rescore
  24. 2026-07-11 08:25 UTCEPSS rescore
  25. 2026-07-09 19:07 UTCEPSS rescore
Show 53 more
  1. 2026-07-09 02:55 UTCNVD updateCVSS v3 → 9.8 · severity → CRITICAL
  2. 2026-07-09 01:31 UTCMITRE cvelistV5
  3. 2026-07-08 15:12 UTCEPSS rescore
  4. 2026-07-07 13:43 UTCEPSS rescore
  5. 2026-07-06 16:25 UTCEPSS rescore
  6. 2026-07-06 16:25 UTCEPSS rescore
  7. 2026-07-06 02:21 UTCEPSS rescore
  8. 2026-07-06 02:21 UTCEPSS rescore
  9. 2026-07-05 17:59 UTCNVD updateCVSS v3 → 9.8 · severity → CRITICAL
  10. 2026-07-05 16:09 UTCMITRE cvelistV5
  11. 2026-07-05 00:28 UTCNVD updateCVSS v3 → 9.8 · severity → CRITICAL
  12. 2026-07-04 23:57 UTCMITRE cvelistV5
  13. 2026-07-04 06:29 UTCEPSS rescore
  14. 2026-07-04 06:29 UTCEPSS rescore
  15. 2026-07-02 16:57 UTCEPSS rescore
  16. 2026-07-01 15:04 UTCEPSS rescore
  17. 2026-06-30 23:20 UTCEPSS rescore
  18. 2026-06-30 23:20 UTCEPSS rescore
  19. 2026-06-28 14:05 UTCEPSS rescore
  20. 2026-06-28 04:54 UTCEPSS rescore
  21. 2026-06-28 04:54 UTCEPSS rescore
  22. 2026-06-27 03:06 UTCEPSS rescore
  23. 2026-06-27 03:06 UTCEPSS rescore
  24. 2026-06-25 13:48 UTCEPSS rescore
  25. 2026-06-25 13:48 UTCEPSS rescore
  26. 2026-06-24 14:03 UTCEPSS rescore
  27. 2026-06-24 14:03 UTCEPSS rescore
  28. 2026-06-23 21:31 UTCEPSS rescore
  29. 2026-06-23 21:31 UTCEPSS rescore
  30. 2026-06-22 14:24 UTCEPSS rescore
  31. 2026-06-21 01:58 UTCEPSS rescore
  32. 2026-06-21 01:58 UTCEPSS rescore
  33. 2026-06-18 17:51 UTCEPSS rescore
  34. 2026-06-18 17:51 UTCEPSS rescore
  35. 2026-06-17 17:51 UTCEPSS rescore
  36. 2026-06-17 17:51 UTCEPSS rescore
  37. 2026-06-17 17:51 UTCEPSS rescore
  38. 2026-06-16 17:51 UTCEPSS rescore
  39. 2026-06-16 17:51 UTCEPSS rescore
  40. 2026-06-15 17:46 UTCEPSS rescore
  41. 2026-06-12 23:10 UTCEPSS rescore
  42. 2026-06-10 22:16 UTCEPSS rescore
  43. 2026-06-10 22:16 UTCEPSS rescore
  44. 2026-06-10 13:20 UTCEPSS rescore
  45. 2026-06-05 22:45 UTCEPSS rescore
  46. 2026-06-04 13:10 UTCEPSS rescore
  47. 2026-06-04 13:10 UTCEPSS rescore
  48. 2026-06-01 13:50 UTCEPSS rescore
  49. 2026-06-01 13:50 UTCEPSS rescore
  50. 2026-05-28 13:43 UTCEPSS rescore
  51. 2026-05-28 13:43 UTCEPSS rescore
  52. 2026-05-26 03:05 UTCEG score recompute
  53. 2026-05-26 03:05 UTCGHSA enrichment

Publicly available exploits

(1 reference)

Working exploit code is in the public domain. Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • Nucleihttp/cves/2021/CVE-2021-45420.yaml
    First seen Jan 1, 2021

    Emerson Dixell XWEB-500 - Arbitrary File Write

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2021-45420?
CVE-2021-45420 is a critical vulnerability published on February 14, 2022. Emerson Dixell XWEB-500 products are affected by arbitrary file write vulnerability in /cgi-bin/logoextraupload.cgi, /cgi-bin/calsave.cgi, and /cgi-bin/loutils.cgi. An attacker will be able to write any file on the target system without any kind of authentication mechanism, and this can lead to…
When was CVE-2021-45420 disclosed?
CVE-2021-45420 was first published in the National Vulnerability Database on February 14, 2022, with the most recent update on July 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-45420 actively exploited?
CVE-2021-45420 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 96.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-45420?
CVE-2021-45420 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2021-45420?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-45420, 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

Explore the affected products and dependency analysis for CVE-2021-45420

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