UnratedFix available
Fix CVE(s): CVE-2026-15308
Type: advisorySources: OSV
* SECURITY UPDATE: CPU denial-of-service in the html.parser module via repeated unterminated markup declarations (quadratic complexity in the incremental HTMLParser) - debian/patches/CVE-2026-15308.patch: accumulate pending data in feed() and parse on a doubling threshold instead of rescanning the whole unparsed buffer each call, in Lib/html/parser.py - CVE-2026-15308
- Products
- idle-python3.5, libpython3.5, libpython3.5-dev, libpython3.5-minimal, libpython3.5-stdlib, libpython3.5-testsuite, python3.5, python3.5-dev, python3.5-doc, python3.5-examples, python3.5-minimal, python3.5-venv
- Affected versions
- Not specified
- Fixed versions
- 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
- CVEs
- CVE-2026-15308
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 11:08 UTC · Revision 1
Source evidence
* SECURITY UPDATE: CPU denial-of-service in the html.parser module via repeated unterminated markup declarations (quadratic complexity in the incremental HTMLParser) - debian/patches/CVE-2026-15308.patch: accumulate pending data in feed() and parse on a doubling threshold instead of rescanning the whole unparsed buffer each call, in Lib/html/parser.py - CVE-2026-15308
osv:CLSA-2026-1784297320
idle-python3.5
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
libpython3.5
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
libpython3.5-dev
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
libpython3.5-minimal
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
libpython3.5-stdlib
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
libpython3.5-testsuite
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
python3.5
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
python3.5-dev
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
python3.5-doc
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
python3.5-examples
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
python3.5-minimal
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
python3.5-venv
Fixed versions: 1:3.5.2-2ubuntu0~16.04.13+tuxcare.els27
Complete source record
{
"id": "7b18761eaa60706a7c13844475915d376ffb88120811057903d9f1fc3dbbe4f2",
"url": "https://osv.dev/vulnerability/CLSA-2026-1784297320",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Fix CVE(s): CVE-2026-15308",
"summary": "* SECURITY UPDATE: CPU denial-of-service in the html.parser module via repeated unterminated markup declarations (quadratic complexity in the incremental HTMLParser) - debian/patches/CVE-2026-15308.patch: accumulate pending data in feed() and parse on a doubling threshold instead of rescanning the whole unparsed buffer each call, in Lib/html/parser.py - CVE-2026-15308",
"evidence": "osv:CLSA-2026-1784297320",
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"evidence": "/affected/0/ranges"
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{
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{
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"evidence": "/affected/9/ranges"
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"affected_versions": []
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{
"name": {
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"evidence": "/affected/10/package/name"
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"evidence": "/affected/10/ranges"
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"affected_versions": []
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{
"name": {
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"evidence": "/affected/11/package/name"
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],
"severity": "unknown",
"structured": {
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"aliases": [
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"database_specific": {
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"database_specific": {
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"ecosystem": "TuxCare:Ubuntu:16.04"
},
"database_specific": {
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"package": {
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"ecosystem": "TuxCare:Ubuntu:16.04"
},
"database_specific": {
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"package": {
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"purl": "pkg:deb/tuxcare/libpython3.5-stdlib?distro=ubuntu-16.04",
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},
"database_specific": {
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"package": {
"name": "libpython3.5-testsuite",
"purl": "pkg:deb/tuxcare/libpython3.5-testsuite?distro=ubuntu-16.04",
"ecosystem": "TuxCare:Ubuntu:16.04"
},
"database_specific": {
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{
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"package": {
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"purl": "pkg:deb/tuxcare/python3.5?distro=ubuntu-16.04",
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"package": {
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"purl": "pkg:deb/tuxcare/python3.5-minimal?distro=ubuntu-16.04",
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},
"database_specific": {
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},
{
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],
"package": {
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"purl": "pkg:deb/tuxcare/python3.5-venv?distro=ubuntu-16.04",
"ecosystem": "TuxCare:Ubuntu:16.04"
},
"database_specific": {
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}
}
],
"modified": "2026-10-26T09:31:46.906781612Z",
"provider": "osv",
"upstream": [
"CVE-2026-15308"
],
"references": [
"https://errata.tuxcare.com/els_os/ubuntu16.04els/CLSA-2026-1784297320.html",
"https://nvd.nist.gov/vuln/detail/CVE-2026-15308"
]
},
"related_cves": [
{
"value": "CVE-2026-15308",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 448460,
"published_at": "2026-07-17T14:09:05+00:00"
}