CVE-2025-66418
urllib3 allows an unbounded number of links in the decompression chain
Description
urllib3 is a user-friendly HTTP client library for Python. Starting in version 1.24 and prior to 2.6.0, the number of links in the decompression chain was unbounded allowing a malicious server to insert a virtually unlimited number of compression steps leading to high CPU usage and massive memory allocation for the decompressed data. This vulnerability is fixed in 2.6.0.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
Red Hat Inc.
commercial·USaka red hat
Fedora Project
oss-project·USaka fedora
python
oss-project·US
urllib3
oss-project
urllib3Library
OSS Libraries / pypiCanonical Ltd.
commercial·GBaka canonical
Сообщество свободного программного обеспечения
oss-projectaka fsf
and 37 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Impact
References
https://github.com/urllib3/urllib3/commit/24d7b67eac89f94e11003424bcf0d8f7b72222a8
github.com
https://github.com/urllib3/urllib3/security/advisories/GHSA-gm62-xv2j-4w53
github.com
https://github.com/urllib3/urllib3/commit/24d7b67eac89f94e11003424bcf0d8f7b72222a8
github.com
and 13 more references View all →
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