CVE-2013-0340

Severity: medium (CVSS 6.8 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 19.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2014-01-21 · updated 2026-10-14
Weakness: CWE-611

Description

expat before version 2.4.0 does not properly handle entities expansion unless an application developer uses the XML_SetEntityDeclHandler function, which allows remote attackers to cause a denial of service (resource consumption), send HTTP requests to intranet servers, or read arbitrary files via a crafted XML document, aka an XML External Entity (XXE) issue. NOTE: it could be argued that because expat already provides the ability to disable external entity expansion, the responsibility for resolving this issue lies with application developers; according to this argument, this entry should be REJECTed, and each affected application would need its own CVE.

Affected products

Apple iPadOS: before 14.8 — fixed in 14.8
Apple Iphone Os: before 14.8 — fixed in 14.8
Apple macOS: before 11.6 — fixed in 11.6
Apple tvOS: before 15.0 — fixed in 15.0
Apple watchOS: before 8.0 — fixed in 8.0
libexpat project libexpat: before 2.4.0 — fixed in 2.4.0
Python: from 3.6.0 before 3.6.15; from 3.7.0 before 3.7.12; from 3.8.0 before 3.8.12; from 3.9.0 before 3.9.7 — fixed in 3.6.15, 3.7.12, 3.8.12, 3.9.7

How to fix

Upgrade to a fixed version: Apple iPadOS 14.8; Apple Iphone Os 14.8; Apple macOS 11.6; Apple tvOS 15.0; Apple watchOS 8.0; libexpat project libexpat 2.4.0; Python 3.6.15, 3.7.12, 3.8.12, 3.9.7. Check the vendor advisory for mitigations.

References

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