5.8

CVE-2026-52761: owasp-modsecurity modsecurity Use of sizeof() on a Pointer Type

CVSS: 5.8v3.1MediumAnalyzed
AliasesUBUNTU-CVE-2026-52761DEBIAN-CVE-2026-52761
Published 10-07-2026Last modified 13-07-2026
Open JSON

Vulnerability summary

CVE-2026-52761 is a medium (CVSS 5.8) Use of sizeof() on a Pointer Type vulnerability in owasp-modsecurity modsecurity. EPSS estimates a 0.41% chance of exploitation in the next 30 days, higher than 33.8% of scored vulnerabilities.

Overall risk
23/100
0100
Low · default modelHow is this calculated?
CVSS score
5.8/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.41%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 10-07-2026
    PublishedVulnerability first disclosed.
  2. 13-07-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.41%

Chance of exploitation in the next 30 days

Percentile

34%

Versus all other CVEs

30-day change

0.00 pp

From 0.41% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.41%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • modsecurityAll versions (No fix recorded) | < 3.0.16-1
Owasp1 product
Owasp-modsecurity1 product
Ubuntu1 product
  • modsecurityAll versions (No fix recorded)

4 vendors · 4 products

References

6 links