CVE-2020-10735

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.

Published: 2022-09-09 Last update: 2025-11-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-10735 is rated Moderate Risk (51/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.40%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-10735

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-28 0.46% 0.40% -0.06%
2 2026-03-26 0.29% 0.46% +0.17%
3 2026-03-21 — 0.29% —

Full EPSS history (26 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-10735

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2020-10735

OS Trackers for CVE-2020-10735

vendor priority summary link
debian not yet assigned CVE-2020-10735 not yet assigned priority: Debian including 4 source packages (pypy3, python2.7, python3.11, python3.9), 8 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 7, open 1. https://security-tracker.debian.org/tracker/CVE-2020-10735
redhat medium — https://access.redhat.com/security/cve/CVE-2020-10735
suse high CVE-2020-10735 severity important: SUSE including 562 source package names (0.0.17-1.1:libpython3_6m1_0-3.6.15-150300.10.37.2, 0.0.17-1.1:python3-3.6.15-150300.10.37.2, …), 2313 product×package rows across 432 product lines (Container bci/bci-base-fips, Container bci/bci-sle15-kernel-module-devel, … (432 product lines)): Fixed 2053, Will Not Fix 139, Known Affected 116, Known Not Affected 5. https://www.suse.com/security/cve/CVE-2020-10735/
ubuntu negligible CVE-2020-10735 negligible priority: Ubuntu including 9 source packages (python, python2.7, …), 56 status rows across 7 suites (bionic, focal, jammy, kinetic, trusty, upstream, xenial): ignored 29, DNE 18, needs-triage 9. https://ubuntu.com/security/CVE-2020-10735

Affected software / configurations for CVE-2020-10735

Vendor Product Version Raw CPE
python python >= 3.7.0, < 3.7.14 cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
python python >= 3.8.0, < 3.8.14 cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
python python >= 3.9.0, < 3.9.14 cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
python python >= 3.10.0, < 3.10.7 cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:alpha1:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:alpha2:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:alpha3:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:alpha4:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:alpha5:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:alpha6:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:alpha7:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:beta1:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:beta2:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:beta3:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:beta4:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:beta5:*:*:*:*:*:*
python python 3.11.0 cpe:2.3:a:python:python:3.11.0:rc1:*:*:*:*:*:*
redhat quay 3.0.0 cpe:2.3:a:redhat:quay:3.0.0:*:*:*:*:*:*:*
redhat software_collections — cpe:2.3:a:redhat:software_collections:-:*:*:*:*:*:*:*
fedoraproject fedora 35 cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
fedoraproject fedora 36 cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*
fedoraproject fedora 37 cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*

References for CVE-2020-10735

URL Tags
http://www.openwall.com/lists/oss-security/2022/09/21/1 Third Party Advisory
http://www.openwall.com/lists/oss-security/2022/09/21/4 Mailing List Third Party Advisory
https://access.redhat.com/security/cve/CVE-2020-10735 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1834423 Issue Tracking Third Party Advisory
https://docs.google.com/document/d/1KjuF_aXlzPUxTK4BMgezGJ2Pn7uevfX7g0_mvgHlL7Y Third Party Advisory
https://github.com/python/cpython/issues/95778 Patch Third Party Advisory
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/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HSRPVJZL6DJFWKYRHMNJB7VCEUCBKRF5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IFGV7P2PYFBMK32OKHCAC2ZPJQV5AUDF/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NHC6IUU7CLRQ3QLPWUXLONSG3SXFTR47/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OKYE2DOI2X7WZXAWTQJZAXYIWM37HDCY/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OT5U223OE5ZOUHZAZYSYSWVJQIKDE73E/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OT5WQB7Z3CXOWVBD2AFAHYPA5ONYFFZ4/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PD7FTLJOIGMUSCDR3JAN6WRFHJEE4PH5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SZYJSGLSCQOKXXFVJVJQAXLEOJBIWGEL/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TD7JDDKJXK6D26XAN3YRFNM2LAJHT5UO/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TMWPRAAJS7I6U3U45V7GZVXWNSECI22M/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U4ZZV4CDFRMTPDBI7C5L43RFL3XLIGUY/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UBPDVCDIUCEBE7C4NAGNA2KQJYOTPBAZ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/V7ZUJDHK7KNG6SLIFXW7MNZ6O2PUJYK6/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WXF6MQ74HVIDDSR5AE2UDR24I6D4FEPC/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZEOAJWGGY55QU35UM2OVZATBW5MX2OZD/
https://lists.debian.org/debian-lts-announce/2024/11/msg00024.html
https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
cvelogic Threat Intelligence