CVE-2025-40632

Browser script execution via crafted lastLogin cookie

Published May 16, 2025 · Updated May 16, 2025

Cross-site scripting in IceWarp Server 11.4.0 allows attackers to execute JavaScript in a user's browser via a crafted lastLogin cookie. The affected page renders the cookie value without neutralizing script content, causing the browser to interpret the supplied value as code. Exploitation requires adjacent-network access and active user interaction; execution is limited to reading or modifying data available in the page's browser context.

CVSS severity6.1
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in IceWarp Server 11.4.0 allows attackers to execute JavaScript in a user's browser via a crafted lastLogin cookie. The affected page renders the cookie value without neutralizing script content, causing the browser to interpret the supplied value as code. Exploitation requires adjacent-network access and active user interaction; execution is limited to reading or modifying data available in the page's browser context.

The record

CVE
CVE-2025-40632
Published
May 16, 2025
Updated
May 16, 2025
Vendor
IceWarp
Product
IceWarp Server
Classifications
CWE-79
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 16, 2025CVE publishedPublication date reported by the CVE source.
  2. May 16, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=11.4.0

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

IceWarp · IceWarp Serverversion=11.4.0

Published CVSS scores

2.0INCIBECVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
6.1NVDCVSS: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.

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No observations available

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

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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