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VULNERABILITIES

CVE-2026-55520 Details

UNDERGOING ENRICHMENT


The CVE is currently being enriched by the Volerion team. The enrichment process results in the association of reference link tags, CVSS, and CPE applicability statement data.

Description

Protego is a pure-Python robots.txt parser with support for modern conventions. Prior to 0.6.2, protego._urlpattern._URLPattern._prepare_pattern_for_regex translates every asterisk in an Allow or Disallow directive into a lazy regular-expression wildcard, so a directive containing many asterisks creates exponential backtracking. After protego.Protego.parse processes a crafted robots.txt file, protego.Protego.can_fetch can spend an attacker-controlled period matching a near-miss URL and deny service to the crawler. The vulnerable path is src/protego/_urlpattern.py in the _URLPattern match logic. This issue is fixed in version 0.6.2.

Metrics

CVSS 3.x Severity and Vector Strings:

NDDVolerionCVSS-B:…Vector:This vulnerability is currently being analyzed.

No CVSS 3.x data is available for this CVE.

References to Advisories, Solutions, and Tools

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Weakness Enumeration

CWE-IDCWE NameSource
CWE-1333Inefficient Regular Expression Complexity[email protected]
CWE-400Uncontrolled Resource Consumption[email protected]

Affected Products

This vulnerability is currently being analyzed

Change History

2 change records found show changes


QUICK INFO

CVE Dictionary Entry:
CVE-2026-55520
NVD Published Date:
Aug 28, 2026
NVD Last Modified:
Sep 9, 2026
Source:
[email protected]
CVE-2026-55520 Details - Not Deferred