CVE-2023-37580Known exploitationPublic exploitNetwork attack vector

Session data theft via unescaped URL parameter

Published Jul 31, 2023 · Updated Oct 30, 2025

Reflected XSS in Zimbra Collaboration 8 before 8.8.15 Patch 41 allows remote attackers to run scripts in the Classic Web Client. The /m/momoveto template writes the URL's st parameter into a hidden input value without XML escaping, allowing injected markup to execute. A logged-in victim must click a crafted link; observed attacks stole mail, credentials, or authentication tokens.

CVSS severity6.1
Medium
EPSS probability46.71%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in Zimbra Collaboration 8 before 8.8.15 Patch 41 allows remote attackers to run scripts in the Classic Web Client. The /m/momoveto template writes the URL's st parameter into a hidden input value without XML escaping, allowing injected markup to execute. A logged-in victim must click a crafted link; observed attacks stole mail, credentials, or authentication tokens.

The record

CVE
CVE-2023-37580
Published
Jul 31, 2023
Updated
Oct 30, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1539, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 29, 2023Exploitation reportedCampaign 1 email-stealing framework
  2. Jul 11, 2023Exploitation reportedWinter Vivern government targeting
  3. Jul 20, 2023Exploitation reportedCampaign 3 credential phishing
  4. Jul 27, 2023Exploitation reportedCISA Known Exploited Vulnerabilities listing
  5. Jul 31, 2023CVE publishedPublication date reported by the CVE source.
  6. Aug 25, 2023Exploitation reportedCampaign 4 authentication-token theft
  7. Oct 30, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
6.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1539Steal Web Session Cookie
T1189Drive-by Compromise

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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