CVE-2026-73856

Read full description

ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 until 3.0.17, src/transaction.cc compares a response Content-Type value against SecResponseBodyMimeType entries case-sensitively. A mixed-case response media type that is semantically equivalent to a configured lowercase type can therefore be treated as unconfigured, causing ModSecurity to skip RESPONSE_BODY inspection. An unauthenticated requester can then receive response content that a phase 4 rule would otherwise block, including sensitive error or debug data. This issue is fixed in version 3.0.17.

CVSS 8.6 (HIGH)

Attention and evidence

HYPE SCORE

0.0/10

REALITY · THREAT PRIORITY

3.0–5.5/10

Missing inputs: range of priority

Evidence confidence: Insufficient evidence

Why this priority?

Technical severity: CVSS 8.6: +3.01

Fresh prediction unavailable

General review priority, not probability, victim count or asset-specific risk. A range covers missing CVSS/EPSS inputs within the current evidence state.

Sources: 1 documents and public datasets.

Hype components

Headline sample (25%)

0/100

Press, 30 days (60%)

0/100

Grounded branding (15%)

0/100

HYPE TOTAL0/100

Sources and documents

Latest Vulnerabilities

Technical advisory · 05 Nov 2026, 16:17 · CVE-2026-73856 - ModSecurity: Response Body Inspection Bypass

Score evolution

● Hype ● Reality

First record: hype 0.0 · reality 3.0 (2026-11-05 17:25). The curve appears once the score changes.

Public exploit evidence

Public exploit entries / repo candidates

Evidence context and dated references

Reality is general threat/review priority, combining observed exploitation, CVSS severity and fresh EPSS. Evidence confidence is separate. This is not calibrated risk, a victim count or an asset-specific assessment. A range reflects missing numeric inputs. Published 1 days ago. Exploitation evidence usually takes weeks to show up: a low reality score can mean there is no data yet, not that the flaw is mild.

Evidence in context

Confidence in exploitation evidence: Insufficient evidence
Priority basis: Exploitation in attacks unconfirmed; CVSS 8.6; fresh prediction unavailable
Attention, last 30 days: 0 distinct story titles; 0 press documents; 0 publisher domains.
Technical potential: network access, no prior privileges, no user interaction.
Observed activity: No exploitation observation is recorded.
Known scale: Not quantified.
Evidence confidence basis: Insufficient evidence

Score evaluated: 2026-11-05 17:25:03.612586+00:00 · EPSS snapshot: not available

Source event timeline

Published

05 Nov 2026, 15:50

Score calculated

05 Nov 2026, 17:25