ModSecurity has possible DoS vulnerability in sanitiseArg action
Priority HIGH 72CWE-1050Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 4 fixed, 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Versions prior to 2.9.10 contain a denial of service vulnerability similar to GHSA-859r-vvv8-rm8r/CVE-2025-47947. The `sanitiseArg` (and `sanitizeArg` - this is the same action but an alias) is vulnerable to adding an excessive number of arguments, thereby leading to denial of service. Version 2.9.10 fixes the issue. As a workaround, avoid using rules that contain the `sanitiseArg` (or `sanitizeArg`) action.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00867 58th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial ModSecurity (owasp-modsecurity): 2.9.10Red Hat: 4 advisoriesRed Hat: 4 fixed, 3 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| owasp-modsecurity | ModSecurity | before 2.9.10 | 2.9.10 | Patch available | CNA |
- ModSecurity Vendorowasp-modsecurity Affected before 2.9.10 Fixed in 2.9.10 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:owasp:modsecurity:*:*:*:*:*:*:*:* | before 2.9.10 | Vulnerable | owasp-modsecurity |
- cpe:2.3:a:owasp:modsecurity:*:*:*:*:*:*:*:* Versions before 2.9.10 Vulnerable ·owasp-modsecurity
Remediation
- Fix · CNA ModSecurity (owasp-modsecurity) Fixed in 2.9.10
Red Hat 4 advisories
- RHSA-2025:13775 Released 2025-08-12 · Red Hat rating Moderatemod_security security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) mod_security-2.9.6-1.el9_2.2, mod_security-mlogc-2.9.6-1.el9_2.2
- RHSA-2025:13716 Released 2025-08-12 · Red Hat rating Moderatemod_security security update
- Red Hat Enterprise Linux AppStream E4S (v.9.0) mod_security-2.9.3-12.el9_0.2, mod_security-mlogc-2.9.3-12.el9_0.2
- RHSA-2025:13670 Released 2025-08-12 · Red Hat rating Moderatemod_security security update
- Red Hat Enterprise Linux AppStream EUS (v.9.4) mod_security-2.9.6-1.el9_4.2, mod_security-mlogc-2.9.6-1.el9_4.2
Show 1 more Red Hat advisories
- RHSA-2025:12838 Released 2025-08-05 · Red Hat rating Moderatemod_security security update
- Red Hat Enterprise Linux AppStream (v. 9) mod_security-2.9.6-2.el9_6.1, mod_security-mlogc-2.9.6-2.el9_6.1
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat JBoss Core Services | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2025:12838 |
| Red Hat Enterprise Linux AppStream E4S (v.9.0) | Fixed | RHSA-2025:13716 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2025:13775 |
| Red Hat Enterprise Linux AppStream EUS (v.9.4) | Fixed | RHSA-2025:13670 |
Timeline
- 2026-10-02 Threatist record created from CVE-2025-48866
References
Patch 1
More owasp-modsecurity Modsecurity vulnerabilities
- TI-2026-37865 ModSecurity: Multipart form-data parser silently strips embedded line breaks from… CVSS 3.1HIGH 8.6
- TI-2026-30581 ModSecurity: Unsigned integer underflow in @verifySSN / @verifyCPF / @verifySVNR operators CVSS 4.0HIGH 8.2
- TI-2026-23748 libModSecurity3 denial of service via segfault when using t:hexDecode on single-character query strings CVSS 4.0HIGH 8.2
- TI-2025-34348 ModSecurity's Insufficient Return Value Handling can Lead to XSS and Source Code Disclosure CVSS 4.0MEDIUM 6.9
- TI-2024-00942 WAF bypass of the ModSecurity v3 release line CVSS 3.1HIGH 8.6
- TI-2023-19686 Trustwave ModSecurity 3.x before 3.0.10 has Inefficient Algorithmic Complexity. CVSS 3.1HIGH 7.5
Sources
- CVE-2025-48866 · CVE Program
- CVE-2025-48866 · NVD
- FIRST EPSS
- CVE-2025-48866 · Red Hat security data · CC BY 4.0
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