`xml.parsers.expat` and `xml.etree.ElementTree` use insufficient entropy for Expat hash-flooding protection, which allows a crafted XML document to trigger hash flooding.\r\n\r\nFully mitigating this vulnerability requires both updating libexpat to 2.8.0 or later and applying this patch.
CVSS Details
- CVSS 4.0 Base Score: 6.3 (MEDIUM)
- CVSS 4.0 Vector: (CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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:X)
- CVSS 3.1 Base Score: 7.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade python3 | Aug 14, 2026 | May 11, 2026 |
| Amazon_linux_2023 | — | Upgrade python3.11-testUpgrade python3.11-debugsourceUpgrade python3.11-idleUpgrade python3.12-tkinterUpgrade python3.12-libsUpgrade python3.11-libsUpgrade python3.12-debugUpgrade python3.12-idleUpgrade python3.12Upgrade python3.12-debugsourceUpgrade python3.12-testUpgrade python3.12-develUpgrade python3.12-debuginfoUpgrade python3.11Upgrade python3.11-debugUpgrade python3.11-develUpgrade python3.11-debuginfoUpgrade python3.11-tkinter | Jul 8, 2026 | May 11, 2026 |
| Ibm Aix | — | Apply the fix or workaround for python_advisory21 | Sep 15, 2026 | Sep 15, 2026 |
| Redhat_linux | — | No solution exists | Jul 17, 2026 | May 11, 2026 |
| Ubuntu | — | Upgrade libpython3.5-minimal (Ubuntu Pro)Upgrade libpython2.7-minimal (Ubuntu Pro)Upgrade python3.5-examples (Ubuntu Pro)Upgrade libpython2.7-testsuite (Ubuntu Pro)Upgrade python2.7-examples (Ubuntu Pro)Upgrade idle-python2.7 (Ubuntu Pro)Upgrade python3.5-minimal (Ubuntu Pro)Upgrade python2.7 (Ubuntu Pro)Upgrade libpython3.5 (Ubuntu Pro)Upgrade python3.5-dev (Ubuntu Pro)Upgrade python3.5-doc (Ubuntu Pro)Upgrade python3.5-venv (Ubuntu Pro)Upgrade libpython3.5-dev (Ubuntu Pro)Upgrade libpython2.7-stdlib (Ubuntu Pro)Upgrade libpython2.7 (Ubuntu Pro)Upgrade libpython3.5-stdlib (Ubuntu Pro)Upgrade python3.5 (Ubuntu Pro)Upgrade libpython3.5-testsuite (Ubuntu Pro)Upgrade libpython2.7-dev (Ubuntu Pro)Upgrade idle-python3.5 (Ubuntu Pro)Upgrade python2.7-dev (Ubuntu Pro)Upgrade python2.7-minimal (Ubuntu Pro)Upgrade python2.7-doc (Ubuntu Pro) | Jul 12, 2026 | Jul 9, 2026 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Jun 19, 2026 | May 11, 2026 |
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