Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-52761— ModSecurity: Transformation utf8toUnicode produces wrong output on i386 architecture

Quick assessment

Affected
owasp-modsecurity ModSecurity
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

owasp-modsecurity ModSecurity是owasp-modsecurity的Web应用防火墙模块。 owasp-modsecurity ModSecurity 3.0.0版本至3.0.15版本存在数字错误漏洞，该漏洞源于t:utf8toUnicode转换中snprintf使用sizeof对字符指针而非unicode缓冲区长度，导致i386架构上输出错误，可能导致使用该转换的规则被绕过。

CVSS 5.8 · Medium EPSS 0.41% · P33

Possible ATT&CK Techniques 1 AI

T1562

Affected Version Matrix 1

VendorProduct Version RangeStatus
owasp-modsecurity ModSecurity >= 3.0.0, < 3.0.16 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-52761

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
ModSecurity: Transformation utf8toUnicode produces wrong output on i386 architecture
Source: CVE Program / CVE List V5
Vulnerability Description
ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 through 3.0.15, the t:utf8toUnicode transformation in src/actions/transformations/utf8_to_unicode.cc produces wrong output on i386 architecture because snprintf uses sizeof on a char pointer rather than the length of the unicode buffer, allowing rules that use this transformation to be bypassed on i386 architecture. This issue is fixed in version 3.0.16.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
在指针类型上使用sizeof()
Source: CVE Program / CVE List V5
Vulnerability Title
owasp-modsecurity ModSecurity 数字错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
owasp-modsecurity ModSecurity是owasp-modsecurity的Web应用防火墙模块。 owasp-modsecurity ModSecurity 3.0.0版本至3.0.15版本存在数字错误漏洞，该漏洞源于t:utf8toUnicode转换中snprintf使用sizeof对字符指针而非unicode缓冲区长度，导致i386架构上输出错误，可能导致使用该转换的规则被绕过。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
owasp-modsecurity ModSecurity >= 3.0.0, < 3.0.16 -

II. Public POCs for CVE-2026-52761

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-52761

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-52761 (1)

Vendor Advisories for CVE-2026-52761 (1)

Other References for CVE-2026-52761 (1)

IV. Related Vulnerabilities

Same product: ModSecurity
Same vendor: owasp-modsecurity
Same weakness: CWE-467

V. Comments for CVE-2026-52761

No comments yet

Leave a comment