UnratedFix available
Fix CVE(s): CVE-2026-19445, CVE-2026-4786
Type: advisorySources: OSV
* SECURITY UPDATE: use-after-free in the ssl module when a servername callback switches the connection to another SSLContext - debian/patches/CVE-2026-19445.patch: look the SSLContext up from the SSL object instead of the borrowed servername-callback argument and hold references to it and to the callback while they are used, and unregister the callback when the context is deallocated, in Modules/_ssl.c, so a TLS client can no longer make the server call through a freed SSLContext; adds the upstream regression tests to Lib/test/test_ssl.py. - CVE-2026-19445
- Products
- idle-python3.6, libpython3.6, libpython3.6-dev, libpython3.6-minimal, libpython3.6-stdlib, libpython3.6-testsuite, python3.6, python3.6-dev, python3.6-doc, python3.6-examples, python3.6-minimal, python3.6-venv
- Affected versions
- Not specified
- Fixed versions
- 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
- CVEs
- CVE-2026-19445, CVE-2026-4786
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 11:42 UTC · Revision 1
Source evidence
* SECURITY UPDATE: use-after-free in the ssl module when a servername callback switches the connection to another SSLContext - debian/patches/CVE-2026-19445.patch: look the SSLContext up from the SSL object instead of the borrowed servername-callback argument and hold references to it and to the callback while they are used, and unregister the callback when the context is deallocated, in Modules/_ssl.c, so a TLS client can no longer make the server call through a freed SSLContext; adds the upstream regression tests to Lib/test/test_ssl.py. - CVE-2026-19445
osv:CLSA-2026-1791820487
idle-python3.6
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
libpython3.6
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
libpython3.6-dev
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
libpython3.6-minimal
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
libpython3.6-stdlib
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
libpython3.6-testsuite
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
python3.6
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
python3.6-dev
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
python3.6-doc
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
python3.6-examples
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
python3.6-minimal
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
python3.6-venv
Fixed versions: 3.6.9-1~18.04ubuntu1.12+tuxcare.els27
Complete source record
{
"id": "e813dd7a5ce0e37033b5adfe9605152aea6014a3bf1fe4c69f144bb3fc24e681",
"url": "https://osv.dev/vulnerability/CLSA-2026-1791820487",
"method": "structured",
"payload": {
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"title": "Fix CVE(s): CVE-2026-19445, CVE-2026-4786",
"summary": "* SECURITY UPDATE: use-after-free in the ssl module when a servername callback switches the connection to another SSLContext - debian/patches/CVE-2026-19445.patch: look the SSLContext up from the SSL object instead of the borrowed servername-callback argument and hold references to it and to the callback while they are used, and unregister the callback when the context is deallocated, in Modules/_ssl.c, so a TLS client can no longer make the server call through a freed SSLContext; adds the upstream regression tests to Lib/test/test_ssl.py. - CVE-2026-19445",
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],
"modified": "2026-10-26T09:32:04.373125890Z",
"provider": "osv",
"upstream": [
"CVE-2026-19445",
"CVE-2026-4786"
],
"references": [
"https://errata.tuxcare.com/els_os/ubuntu18.04els/CLSA-2026-1791820487.html",
"https://nvd.nist.gov/vuln/detail/CVE-2026-19445",
"https://nvd.nist.gov/vuln/detail/CVE-2026-4786"
]
},
"related_cves": [
{
"value": "CVE-2026-19445",
"evidence": "/upstream"
},
{
"value": "CVE-2026-4786",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 449607,
"published_at": "2026-10-19T20:55:08+00:00"
}