What’s Vulnerable › Vulnerabilities

CVE-2020-10735

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 4.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2022-09-09 · updated 2026-10-14
• Weakness: CWE-704

Description

A flaw was found in python. In algorithms with quadratic time complexity using non-binary bases, when using int("text"), a system could take 50ms to parse an int string with 100,000 digits and 5s for 1,000,000 digits (float, decimal, int.from_bytes(), and int() for binary bases 2, 4, 8, 16, and 32 are not affected). The highest threat from this vulnerability is to system availability.

Affected products

• Fedoraproject Fedora: 35, 36, 37
• Python: from 3.7.0 before 3.7.14; from 3.8.0 before 3.8.14; from 3.9.0 before 3.9.14; from 3.10.0 before 3.10.7; 3.11.0-alpha1, 3.11.0-alpha2, 3.11.0-alpha3, 3.11.0-alpha4, 3.11.0-alpha5, 3.11.0-alpha6 (+7) — fixed in 3.10.7, 3.7.14, 3.8.14, 3.9.14
• Red Hat Enterprise Linux: 8.0
• Red Hat Quay 3: 3.0.0
• RedHat Software Collections: all versions

How to fix

Upgrade to a fixed version: Python 3.10.7, 3.7.14, 3.8.14, 3.9.14. Check the vendor advisory for mitigations.

References

• http://www.openwall.com/lists/oss-security/2022/09/21/1
• http://www.openwall.com/lists/oss-security/2022/09/21/4
• https://access.redhat.com/security/cve/CVE-2020-10735
• https://bugzilla.redhat.com/show_bug.cgi?id=1834423
• https://docs.google.com/document/d/1KjuF_aXlzPUxTK4BMgezGJ2Pn7uevfX7g0_mvgHlL7Y
• https://github.com/python/cpython/issues/95778
• https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2VCU6EVQDIXNCEDJUCTFIER2WVNNDTYZ/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/32AAQKABEKFCB5DDV5OONRZK6BS23HPW/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4EWKR2SPX3JORLWCXFY3KN2U5B5CIUQQ/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6XL6E5A3I36TRR73VNBOXNIQP4AMZDFZ/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/76YE7AM37MRU76XJV4M27CWDAMUGNRYK/

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