CVE-2026-9769 (GCVE-0-2026-9769)

Vulnerability from cvelistv5 – Published: 2026-08-23 13:34 – Updated: 2026-08-24 17:54
VLAI
Title
justhtml before 1.10.0 Denial of Service via deeply nested HTML
Summary
justhtml through 1.9.1 (fixed in 1.10.0) is vulnerable to uncontrolled recursion leading to denial of service. During JustHTML() construction, TreeBuilder.finish() unconditionally calls _populate_selectedcontent(), which recursively traverses the DOM tree via _find_elements()/_find_element() without a depth bound. An attacker who can supply HTML for parsing can provide deeply nested elements (e.g., ~1000 nested <div> tags, roughly 11 KB) to exceed CPython's default recursion limit and trigger an unhandled RecursionError, which may abort parsing, fail requests, or terminate a worker/process depending on the host application's exception handling.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-24 17:53 UTC
CWE
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6373 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
EmilStenstrom justhtml Affected: 0 , < 1.10.0 (semver)
Unaffected: 1.10.0 (semver)
guessed Create a notification for this product.
Date Public
2026-03-15 00:00
Credits
kq5y
Show details on NVD website
To clipboard 

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