Packages
- python-urllib3 - HTTP library with thread-safe connection pooling
Details
Illia Volochii discovered that urllib3 did not limit the steps in a
decompression chain. An attacker could possibly use this issue to cause
urllib3 to use excessive resources, causing a denial of service.
(CVE-2025-66418)
Rui Xi discovered that urllib3 incorrectly handled highly compressed data.
An attacker could possibly use this issue to cause urllib3 to use excessive
resources, causing a denial of service. This issue only affected Ubuntu
24.04 LTS, Ubuntu 25.04, and Ubuntu 25.10. (CVE-2025-66471)
For the brotli encoding, the fix for CVE-2025-66471 requires an additional
security update in the brotli package.
Illia Volochii discovered that urllib3 did not limit the steps in a
decompression chain. An attacker could possibly use this issue to cause
urllib3 to use excessive resources, causing a denial of service.
(CVE-2025-66418)
Rui Xi discovered that urllib3 incorrectly handled highly compressed data.
An attacker could possibly use this issue to cause urllib3 to use excessive
resources, causing a denial of service. This issue only affected Ubuntu
24.04 LTS, Ubuntu 25.04, and Ubuntu 25.10. (CVE-2025-66471)
For the brotli encoding, the fix for CVE-2025-66471 requires an additional
security update in the brotli package.
Update instructions
In general, a standard system update will make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
| Ubuntu Release | Package Version | ||
|---|---|---|---|
| 25.10 questing | python3-urllib3 – 2.3.0-3ubuntu0.1 | ||
| 25.04 plucky | python3-urllib3 – 2.3.0-2ubuntu0.2 | ||
| 24.04 LTS noble | python3-urllib3 – 2.0.7-1ubuntu0.3 | ||
| 22.04 LTS jammy | python3-urllib3 – 1.26.5-1~exp1ubuntu0.4 | ||
| 20.04 LTS focal | python3-urllib3 – 1.25.8-2ubuntu0.4+esm2 | ||
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