Vulnerability Lookup

🛡️ UBUNTU-CVE-2021-3737

⚪ Unknown ✅ No Known Exploit OSV

N/A

CVSS Score

0 Low4 Medium7 High9 Critical10

Description

A flaw was found in python. An improperly handled HTTP response in the HTTP client code of python may allow a remote attacker, who controls the HTTP server, to make the client script enter an infinite loop, consuming CPU time. The highest threat from this vulnerability is to system availability.

Details

Severity Unknown

CVSS Score N/A

CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE N/A

Public Exploit ✅ No

Source OSV

Published 2021-08-31

Updated 2026-06-15

Modified 2026-04-22

Fix URL N/A

Affected Packages

Software	From version	Fixed in
python3.4	—	3.4.3-1ubuntu1~14.04.7+esm11
python3.5	—	3.5.2-2ubuntu0~16.04.13+esm1
python3.6	—	3.6.9-1~18.04ubuntu1.6
python3.7	—	3.7.5-2ubuntu1~18.04.2
python3.8	—	3.8.10-0ubuntu1~20.04.2
python3.9	—	3.9.5-3ubuntu0~20.04.1

References

REPORT https://ubuntu.com/security/CVE-2021-3737

REPORT https://bugs.python.org/issue44022

REPORT https://github.com/python/cpython/pull/25916

REPORT https://github.com/python/cpython/pull/26503

REPORT https://github.com/python/cpython/commit/60ba0b68470a584103e28958d91e93a6db37ec92

REPORT https://github.com/python/cpython/commit/ea9327036680acc92d9f89eaf6f6a54d2f8d78d9

REPORT https://github.com/python/cpython/commit/f396864ddfe914531b5856d7bf852808ebfc01ae

REPORT https://github.com/python/cpython/commit/078b146f062d212919d0ba25e34e658a8234aa63

REPORT https://github.com/python/cpython/commit/f68d2d69f1da56c2aea1293ecf93ab69a6010ad7

REPORT https://github.com/python/cpython/commit/98e5a7975d99b58d511f171816ecdfb13d5cca18

REPORT https://github.com/python/cpython/commit/5df4abd6b033a5f1e48945c6988b45e35e76f647

REPORT https://github.com/python/cpython/commit/0389426fa4af4dfc8b1d7f3f291932d928392d8b

REPORT https://github.com/python/cpython/commit/fee96422e6f0056561cf74fef2012cc066c9db86

REPORT https://github.com/python/cpython/commit/1b6f4e5e13ebd1f957b47f7415b53d0869bdbac6

ADVISORY https://ubuntu.com/security/notices/USN-5083-1

ADVISORY https://ubuntu.com/security/notices/USN-5199-1

ADVISORY https://ubuntu.com/security/notices/USN-5200-1

ADVISORY https://ubuntu.com/security/notices/USN-5201-1

REPORT https://www.cve.org/CVERecord?id=CVE-2021-3737

ADVISORY https://ubuntu.com/security/notices/USN-6891-1

🔗 NVD 🔗 Mitre

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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