CVE-2025-27088Public exploitNetwork attack vector

Browser script execution via unescaped request path

Published Feb 20, 2025 · Updated Feb 21, 2025

Reflected XSS in the folder-list template in Oxyno-zeta S3-Proxy before 4.18.0 allows remote attackers to execute script via a crafted URL. The template renders Request.URL.Path directly with Go text/template, leaving injected HTML and JavaScript unescaped in the generated page. Exploitation requires a user to visit the malicious URL, after which script runs in that user's browser context and can expose session data or support phishing.

CVSS severity8.4
High
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in the folder-list template in Oxyno-zeta S3-Proxy before 4.18.0 allows remote attackers to execute script via a crafted URL. The template renders Request.URL.Path directly with Go text/template, leaving injected HTML and JavaScript unescaped in the generated page. Exploitation requires a user to visit the malicious URL, after which script runs in that user's browser context and can expose session data or support phishing.

The record

CVE
CVE-2025-27088
Published
Feb 20, 2025
Updated
Feb 21, 2025
Vendor
Oxyno-zeta
Product
S3-Proxy
Classifications
CWE-79, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 20, 2025CVE publishedPublication date reported by the CVE source.
  2. Feb 21, 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=< 4.18.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oxyno-zeta · S3-Proxyversion=< 4.18.0

Published CVSS scores

8.4GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:H/SI:H/SA: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1566.002Spearphishing Link

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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