Microsoft · In libexpat through 2.7.3, a crafted file with an approximate size of 2 MiB can lead to dozens of seconds of
Affects MicrosoftSource GCVE Database
Not known to be exploited · CVSS 2.9 Low : upgrade to 2.7.4 when convenient.
Data as of 30 Oct 2026, 07:51 UTC
- Patch
- Available – fixed in 2.7.4
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 28 Nov 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade libexpat/libexpat to 2.7.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| libexpat projectlibexpat | Affected
| Fixed in– |
GitHublibexpat/libexpatpkg:github/libexpat/libexpatOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
CVE-2025-66382 is a vulnerability in libexpat through version 2.7.3 where processing a crafted file of approximately 2 MiB can cause a significant delay lasting dozens of seconds. The vulnerability is associated with CWE-407 (Improper Resource Shutdown or Release). No CVSS score or detailed impact metrics are provided.