CVE-2026-33511

pyload-ng: Authentication Bypass via Host Header Injection in ClickNLoad

Published Mar 24, 2026 CVSS 4.0 · 8.8 High EPSS < 1% KEV · Not listed
Description
pyLoad is a free and open-source download manager written in Python. From version 0.4.20 to before version 0.5.0b3.dev97, the local_check decorator in pyLoad's ClickNLoad feature can be bypassed by any remote attacker through HTTP Host header spoofing. This allows unauthenticated remote users to access localhost-restricted endpoints, enabling them to inject arbitrary downloads, write files to the storage directory, and execute JavaScript code. This issue has been patched in version 0.5.0b3.dev97.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Pyload-ng Project
Pyload-ng Project pyload-ng
CPEs cpe:2.3:a:pyload-ng_project:pyload-ng:*:*:*:*:*:python:*:*
cpe:2.3:a:pyload:pyload:*:*:*:*:*:*:*:*
Vendors & Products Pyload-ng Project
Pyload-ng Project pyload-ng
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Pyload
Pyload pyload
Vendors & Products Pyload
Pyload pyload
Type Values Removed Values Added
Description pyLoad is a free and open-source download manager written in Python. From version 0.4.20 to before version 0.5.0b3.dev97, the local_check decorator in pyLoad's ClickNLoad feature can be bypassed by any remote attacker through HTTP Host header spoofing. This allows unauthenticated remote users to access localhost-restricted endpoints, enabling them to inject arbitrary downloads, write files to the storage directory, and execute JavaScript code. This issue has been patched in version 0.5.0b3.dev97.
Title pyload-ng: Authentication Bypass via Host Header Injection in ClickNLoad
Weaknesses CWE-639
References
Metrics cvssV4_0

{'score': 8.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:L/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Mar 25, 2026, 2:28 PM
Reserved
Mar 20, 2026, 4:59 PM
Status
Analyzed
Published
Mar 24, 2026, 8:16 PM
Modified
Jun 17, 2026, 10:37 AM