python: Fix of 2 CVEs
- CVE-2021-3733: fix ReDoS in urllib2 AbstractBasicAuthHandler regex; the legacy '(?:.*,)*' prefix is replaced with the upstream-3.x form '(?:^|,)' and the scheme charset excludes ',' to prevent quadratic backtracking on crafted WWW-Authenticate headers - CVE-2021-23336: stop accepting ';' as a default query-string separator in urlparse.parse_qs/parse_qsl and cgi.parse* / FieldStorage; only '&' is used by default, with an opt-in 'separator' kwarg for callers that need legacy behavior - Additional tests for CVE-2021-23336: drop obsolete legacy-';' entries from Lib/test/test_cgi.py parse_strict_test_cases
- Products
- python, python-debug, python-devel, python-libs, python-test, python-tools, tkinter
- Affected versions
- Not specified
- Fixed versions
- 2.7.5-94.0.1.el7_9.tuxcare.els8
- CVEs
- CVE-2021-23336, CVE-2021-3733
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 14:07 UTC · Revision 1
Source evidence
- CVE-2021-3733: fix ReDoS in urllib2 AbstractBasicAuthHandler regex; the legacy '(?:.*,)*' prefix is replaced with the upstream-3.x form '(?:^|,)' and the scheme charset excludes ',' to prevent quadratic backtracking on crafted WWW-Authenticate headers - CVE-2021-23336: stop accepting ';' as a default query-string separator in urlparse.parse_qs/parse_qsl and cgi.parse* / FieldStorage; only '&' is used by default, with an opt-in 'separator' kwarg for callers that need legacy behavior - Additional tests for CVE-2021-23336: drop obsolete legacy-';' entries from Lib/test/test_cgi.py parse_strict_test_cases
osv:CLSA-2026-1778505256
python
Fixed versions: 2.7.5-94.0.1.el7_9.tuxcare.els8
python-debug
Fixed versions: 2.7.5-94.0.1.el7_9.tuxcare.els8
python-devel
Fixed versions: 2.7.5-94.0.1.el7_9.tuxcare.els8
python-libs
Fixed versions: 2.7.5-94.0.1.el7_9.tuxcare.els8
python-test
Fixed versions: 2.7.5-94.0.1.el7_9.tuxcare.els8
python-tools
Fixed versions: 2.7.5-94.0.1.el7_9.tuxcare.els8
tkinter
Fixed versions: 2.7.5-94.0.1.el7_9.tuxcare.els8
Complete source record
{
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"modified": "2026-10-21T10:48:13.072042996Z",
"provider": "osv",
"upstream": [
"CVE-2021-23336",
"CVE-2021-3733"
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"source_id": "core-osv",
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"published_at": "2026-05-11T13:14:21+00:00"
}