CVE-2024-27306Network attack vector

Stored XSS via unescaped static-index filenames

Published Apr 18, 2024 · Updated Nov 3, 2025

Cross-site scripting in aiohttp before 3.9.4 allows remote attackers to execute script in a user's browser via a static index page. StaticResource._directory_as_html inserts filenames and relative paths directly into generated HTML without escaping or URL quoting. Exploitation requires show_index=True, attacker-controlled filenames in the served directory, and user interaction with the resulting index page.

CVSS severity6.1
Medium
EPSS probability0.67%
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 aiohttp before 3.9.4 allows remote attackers to execute script in a user's browser via a static index page. StaticResource._directory_as_html inserts filenames and relative paths directly into generated HTML without escaping or URL quoting. Exploitation requires show_index=True, attacker-controlled filenames in the served directory, and user interaction with the resulting index page.

The record

CVE
CVE-2024-27306
Published
Apr 18, 2024
Updated
Nov 3, 2025
Vendor
aio-libs
Product
aiohttp
Classifications
CWE-79, CWE-80, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 18, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 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=0 <3.9.4
  2. Affected versionversion=< 3.9.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

aio-libs · aiohttpversion=0 <3.9.4; version=< 3.9.4

Published CVSS scores

6.1GitHub, Inc.CVSS: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 exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-80Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
T1203Exploitation for Client Execution

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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