CVE-2026-115355

Mistune before 3.3.0 Path Traversal and XSS via Include Directive

HIGH
7.5
CVSS Score
Published: October 22, 2026 at 07:13 PM UTC
Updated: October 29, 2026 at 02:17 PM UTC
1 product affected across 1 vendorProject Mistune

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Severity
HIGH7.5
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versions
Vendor states this is fixed in 3.3.0 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHVulnCheck
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-22

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