CVE-2023-37580

CRITICALNVD 6.19.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2023-07-27), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 6.1 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, nvd
Trending — 4 sources updated this weekExploited in the wild
9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 49%CVSS: 6.1Exploit: cisa kev · ssvc active · epss top5pct · public exploitExposed: 0

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

Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client.

CVSS v3
6.1
EG Score
9.0(high)
EG Risk
81(Attend)
EG Risk 81/100SSVC: Attend

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
Severity90% × 45%
Exploitation100% × 40%
Automatability0% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
49%
EPSS %ILE
99%
KEV
⚠ Exploited

Published

July 31, 2023

Last Modified

October 31, 2025

Advisory Details (4)

Auto-updated Jun 13, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: cisa.
cisa Patch Available🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-37580
generic

Zimbra Responsible Disclosure Policy - Zimbra :: Tech Center

https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy
generic🔴 Active Exploitation

Security Center - Zimbra :: Tech Center

https://wiki.zimbra.com/wiki/Security_Center
generic🔴 Active Exploitation

oss-security - CVE-2023-37580 (and others): XSS vulnerabilities in Zimbra Collaboration Suite

http://www.openwall.com/lists/oss-security/2023/11/17/2

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 59× in last 7d / 245× 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 937 total refreshes for this CVE.

  1. 2026-09-25 14:55 UTCCISA KEV update
  2. 2026-09-25 12:31 UTCGHSA enrichment
  3. 2026-09-25 08:42 UTCGHSA enrichment
  4. 2026-09-25 04:53 UTCGHSA enrichment
  5. 2026-09-25 01:04 UTCGHSA enrichment
  6. 2026-09-24 21:14 UTCGHSA enrichment
  7. 2026-09-24 19:31 UTCCISA KEV update
  8. 2026-09-24 17:25 UTCEG score recompute
  9. 2026-09-24 17:25 UTCGHSA enrichment
  10. 2026-09-24 14:01 UTCEPSS rescore
  11. 2026-09-24 14:01 UTCEPSS rescore
  12. 2026-09-24 13:36 UTCGHSA enrichment
  13. 2026-09-24 09:47 UTCGHSA enrichment
  14. 2026-09-24 05:57 UTCGHSA enrichment
  15. 2026-09-24 02:07 UTCGHSA enrichment
  16. 2026-09-23 22:18 UTCGHSA enrichment
  17. 2026-09-23 18:28 UTCGHSA enrichment
  18. 2026-09-23 14:39 UTCEG score recompute
  19. 2026-09-23 14:39 UTCGHSA enrichment
  20. 2026-09-23 13:45 UTCEPSS rescore
  21. 2026-09-23 10:49 UTCGHSA enrichment
  22. 2026-09-23 07:00 UTCGHSA enrichment
  23. 2026-09-23 03:11 UTCGHSA enrichment
  24. 2026-09-22 23:21 UTCGHSA enrichment
  25. 2026-09-22 19:36 UTCCISA KEV update
Show 75 more
  1. 2026-09-22 19:29 UTCGHSA enrichment
  2. 2026-09-22 15:40 UTCEG score recompute
  3. 2026-09-22 15:40 UTCGHSA enrichment
  4. 2026-09-22 14:45 UTCEPSS rescore
  5. 2026-09-22 11:50 UTCGHSA enrichment
  6. 2026-09-22 08:01 UTCGHSA enrichment
  7. 2026-09-22 04:12 UTCGHSA enrichment
  8. 2026-09-22 00:23 UTCGHSA enrichment
  9. 2026-09-21 20:34 UTCEG score recompute
  10. 2026-09-21 20:34 UTCGHSA enrichment
  11. 2026-09-21 19:09 UTCCISA KEV update
  12. 2026-09-21 16:45 UTCGHSA enrichment
  13. 2026-09-21 12:55 UTCGHSA enrichment
  14. 2026-09-21 09:06 UTCGHSA enrichment
  15. 2026-09-21 05:16 UTCGHSA enrichment
  16. 2026-09-21 01:26 UTCGHSA enrichment
  17. 2026-09-20 21:37 UTCGHSA enrichment
  18. 2026-09-20 17:47 UTCGHSA enrichment
  19. 2026-09-20 13:58 UTCGHSA enrichment
  20. 2026-09-20 10:09 UTCGHSA enrichment
  21. 2026-09-20 06:20 UTCGHSA enrichment
  22. 2026-09-20 02:30 UTCGHSA enrichment
  23. 2026-09-19 22:41 UTCGHSA enrichment
  24. 2026-09-19 18:52 UTCEG score recompute
  25. 2026-09-19 18:52 UTCGHSA enrichment
  26. 2026-09-19 15:02 UTCGHSA enrichment
  27. 2026-09-19 11:09 UTCGHSA enrichment
  28. 2026-09-19 07:20 UTCGHSA enrichment
  29. 2026-09-19 03:30 UTCGHSA enrichment
  30. 2026-09-18 23:41 UTCGHSA enrichment
  31. 2026-09-18 19:52 UTCEG score recompute
  32. 2026-09-18 19:52 UTCGHSA enrichment
  33. 2026-09-18 19:20 UTCCISA KEV update
  34. 2026-09-18 16:02 UTCGHSA enrichment
  35. 2026-09-18 14:15 UTCCISA KEV update
  36. 2026-09-18 12:10 UTCGHSA enrichment
  37. 2026-09-18 08:20 UTCGHSA enrichment
  38. 2026-09-18 04:30 UTCGHSA enrichment
  39. 2026-09-18 00:41 UTCGHSA enrichment
  40. 2026-09-17 20:52 UTCEG score recompute
  41. 2026-09-17 20:52 UTCGHSA enrichment
  42. 2026-09-17 17:02 UTCGHSA enrichment
  43. 2026-09-17 12:43 UTCGHSA enrichment
  44. 2026-09-17 08:53 UTCGHSA enrichment
  45. 2026-09-17 05:03 UTCGHSA enrichment
  46. 2026-09-17 01:13 UTCGHSA enrichment
  47. 2026-09-16 21:24 UTCGHSA enrichment
  48. 2026-09-16 17:34 UTCEG score recompute
  49. 2026-09-16 17:34 UTCGHSA enrichment
  50. 2026-09-16 14:10 UTCCISA KEV update
  51. 2026-09-16 14:05 UTCEPSS rescore
  52. 2026-09-16 13:44 UTCGHSA enrichment
  53. 2026-09-16 09:53 UTCGHSA enrichment
  54. 2026-09-16 06:03 UTCEG score recompute
  55. 2026-09-16 06:03 UTCGHSA enrichment
  56. 2026-09-16 02:13 UTCGHSA enrichment
  57. 2026-09-15 22:22 UTCGHSA enrichment
  58. 2026-09-15 18:32 UTCGHSA enrichment
  59. 2026-09-15 14:43 UTCGHSA enrichment
  60. 2026-09-15 10:54 UTCGHSA enrichment
  61. 2026-09-15 07:03 UTCGHSA enrichment
  62. 2026-09-15 03:13 UTCEG score recompute
  63. 2026-09-15 03:13 UTCGHSA enrichment
  64. 2026-09-14 23:24 UTCGHSA enrichment
  65. 2026-09-14 19:35 UTCGHSA enrichment
  66. 2026-09-14 19:24 UTCCISA KEV update
  67. 2026-09-14 15:46 UTCGHSA enrichment
  68. 2026-09-14 11:57 UTCGHSA enrichment
  69. 2026-09-14 08:07 UTCGHSA enrichment
  70. 2026-09-14 04:17 UTCGHSA enrichment
  71. 2026-09-14 00:28 UTCGHSA enrichment
  72. 2026-09-13 20:39 UTCGHSA enrichment
  73. 2026-09-13 16:50 UTCGHSA enrichment
  74. 2026-09-13 13:00 UTCGHSA enrichment
  75. 2026-09-13 09:11 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/2023/CVE-2023-37580.yaml
    First seen Jan 1, 2023

    Zimbra Collaboration Suite (ZCS) v.8.8.15 - Cross-Site Scripting

    Open source ↗

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2023-37580?
CVE-2023-37580 is a critical vulnerability published on July 31, 2023. Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client.
When was CVE-2023-37580 disclosed?
CVE-2023-37580 was first published in the National Vulnerability Database on July 31, 2023, with the most recent update on October 31, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2023-37580 actively exploited?
Yes. CISA added CVE-2023-37580 to the Known Exploited Vulnerabilities catalog on July 27, 2023, affecting Synacor Zimbra Collaboration Suite (ZCS). KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2023-37580?
CVE-2023-37580 has a CVSS v3 base score of 6.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2023-37580?
CVE-2023-37580 affects Synacor Zimbra Collaboration Suite (ZCS). The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2023-37580?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-37580, 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-2023-37580

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