CVE-2026-15308

highpriority · track · 30EPSS 0.006 · 50 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.64% (50th) EPSS

CVSS 7.5 · high

Is it mine?

42 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-22

The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.

cvss

Technical severity, 0–10. One row per scoring source.

8.7

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v4.08.7highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU

v4.08.7highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · cna@python.org

v4.06.6mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400US

affected products (42)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Fedora Linuxall versionscert_bundDEcpe:/o:fedoraproject:fedora:-
Google Container-Optimized OSall versionscert_bundDEcpe:/o:google:container-optimized_os:-
IBM AIX 7.3all versionscert_bundDEcpe:/o:ibm:aix:7.3
IBM VIOS 4.1all versionscert_bundDEcpe:/a:ibm:vios:4.1
Microsoft Azure Linux azl3all versionscert_bundDEcpe:/o:microsoft:azure_linux:azl3
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxall versionscert_bundDEcpe:/o:resf:rocky_linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
SUSE openSUSEall versionscert_bundDEcpe:/o:suse:opensuse:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Dell Secure Connect Gateway< 5.36.00.16cert_bundDE
Open Source Python≤ CPython <=3.15.0cert_bundDE
Python Software Foundation CPython0 → 3.10.21enisa_euvdEU
Python Software Foundation CPython3.11.0 → 3.11.16enisa_euvdEU
Python Software Foundation CPython3.12.0 → 3.12.14enisa_euvdEU
Python Software Foundation CPython3.13.0 → 3.13.15enisa_euvdEU
Python Software Foundation CPython3.14.0 → 3.14.7enisa_euvdEU

showing 20 of 42

advisories (7)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-2272CPython: Schwachstelle ermöglicht Denial of ServiceDeutsch2026-07-09csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in CPython ausnutzen, um einen Denial of Service Angriff durchzuführen.
WID-SEC-W-2026-2919IBM App Connect Enterprise: Mehrere SchwachstellenDeutsch2026-08-18csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM App Connect Enterprise ausnutzen, um beliebigen Programmcode auszuführen, um seine Privilegien zu erhöhen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen, und um Sicherheitsvorkehrungen zu umgehen.
WID-SEC-W-2026-3043IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2026-08-26csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um seine Privilegien zu erhöhen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen und um beliebigen Programmcode auszuführen.
BIT-libpython-2026-15308Incremental HTMLParser feed() allows CPU-exhaustion DoS via repeated unterminated markup declarations2026-08-19vendor · osvUS
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
BIT-python-2026-15308Incremental HTMLParser feed() allows CPU-exhaustion DoS via repeated unterminated markup declarations2026-08-19vendor · osvUS
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
BIT-python-min-2026-15308Incremental HTMLParser feed() allows CPU-exhaustion DoS via repeated unterminated markup declarations2026-08-19vendor · osvUS
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
PSF-2026-332026-07-09vendor · osvUS
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.

also known as (7)

Other names and identifiers for this entity.

CNNVD-2026-56607646 cnnvd
EUVD-2026-42638 enisa_euvd
GHSA-7qj2-q5c8-cxx5 enisa_euvd
BIT-libpython-2026-15308osv
BIT-python-2026-15308osv
BIT-python-min-2026-15308osv
PSF-2026-33osv

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv cert_bund NVD CVE.org MITRE

published 2026-07-09modified 2026-08-20

references (30)

External citations — patches, advisories, analysis.

scry

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