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XML External Entity (XXE) Injection in OWSLib

High
tomkralidis published GHSA-8h9c-r582-mggc Mar 6, 2023

Package

pip OWSLib (pip)

Affected versions

< 0.28.1

Patched versions

0.28.1

Description

Impact

OWSLib's XML parser (which supports both lxml and xml.etree) does not disable entity resolution for lxml, and could lead to arbitrary file reads from an attacker-controlled XML payload. This affects all XML parsing in the codebase.

Patches

  • Use only lxml for XML handling, adding resolve_entities=False to lxml's parser: #863

Workarounds

patch_well_known_namespaces(etree)
etree.set_default_parser(
    parser=etree.XMLParser(resolve_entities=False)
)

References

Severity

High
8.2
/ 10

CVSS base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
Low
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:L

CVE ID

CVE-2023-27476

Weaknesses

Credits