Skip to content

pyLoad has an Arbitrary File Write via Path Traversal in edit_package()

High severity GitHub Reviewed Published Mar 4, 2026 in pyload/pyload • Updated Jun 8, 2026

Package

pip pyload-ng (pip)

Affected versions

>= 0.5.0b3.dev13, <= 0.5.0b3.dev96

Patched versions

0.5.0b3.dev97

Description

The edit_package() function implements insufficient sanitization for the pack_folder parameter. The current protection relies on a single-pass string replacement of "../", which can be bypassed using crafted recursive traversal sequences.

Exploitation

An authenticated user with MODIFY permission can bypass the sanitization by submitting a payload such as:
pack_folder=..././..././..././tmp

After the single-pass replacement, this becomes:
../../../tmp

Because the traversal sequences are not properly validated, the resulting normalized path escapes the intended storage directory and writes files to /tmp or other locations.

References

@GammaC0de GammaC0de published to pyload/pyload Mar 4, 2026
Published to the GitHub Advisory Database Mar 5, 2026
Reviewed Mar 5, 2026
Published by the National Vulnerability Database Mar 7, 2026
Last updated Jun 8, 2026

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
Low

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

EPSS score

Exploit Prediction Scoring System (EPSS)

This score estimates the probability of this vulnerability being exploited within the next 30 days. Data provided by FIRST.
(41st percentile)

Weaknesses

Relative Path Traversal

The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as .. that can resolve to a location that is outside of that directory. Learn more on MITRE.

CVE ID

CVE-2026-29778

GHSA ID

GHSA-6px9-j4qr-xfjw

Source code

Credits

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.