libexpat versions 2.7.2 through 2.8.5 contain an integer overflow vulnerability in expat_realloc() function on 32-bit platforms when computing allocation sizes. Attackers supplying malicious XML to applications parsing with vulnerable libexpat can cause heap buffer overflow, memory corruption, or denial of service.
CVSS Details
- CVSS 4.0 Base Score: 8.2 (HIGH)
- CVSS 4.0 Vector: (CVSS:4.0/AV:N/AC:H/AT:P/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:X)
- CVSS 3.1 Base Score: 5.9
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade expat-develUpgrade expat | Oct 25, 2026 | Oct 22, 2026 |
| Alpine Linux | — | Upgrade expat | Oct 20, 2026 | Sep 29, 2026 |
| Amazon Linux Ami 2 | — | Upgrade firefox | Oct 19, 2026 | Oct 19, 2026 |
| Amazon_linux_2023 | — | Upgrade firefoxUpgrade firefox-debuginfoUpgrade firefox-debugsource | Oct 13, 2026 | Sep 29, 2026 |
| Debian | — | Upgrade expat | Oct 20, 2026 | Sep 29, 2026 |
| Ibm Aix | — | Apply the fix or workaround for python_advisory22 | Oct 21, 2026 | Oct 21, 2026 |
| Oracle_linux | — | Upgrade expatUpgrade expat-devel | Oct 28, 2026 | Sep 29, 2026 |
| Redhat_linux | — | Upgrade expat-debugsourceUpgrade expat-debuginfoUpgrade expatUpgrade expat-develNo solution exists | Oct 1, 2026 | Sep 29, 2026 |
| Rocky_linux | — | Upgrade expat-debugsourceUpgrade expat-debuginfoUpgrade expatUpgrade expat-devel | Oct 26, 2026 | Oct 23, 2026 |
Prioritize with Active Threat Intelligence
With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.
Explore Intelligence Hub