CVE-2026-11564Haxx Curl
NVDCVSS scored by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Vulnerability Summary
libcurl keeps previously used connections in a connection pool for subsequent
transfers to reuse if one of them matches the setup.
An easy handle that first uses default native CA trust can continue trusting
the native platform store after the application switches that same handle to
custom CA material for a later transfer.
transfers to reuse if one of them matches the setup.
An easy handle that first uses default native CA trust can continue trusting
the native platform store after the application switches that same handle to
custom CA material for a later transfer.
CVSS v3.1 Base Metrics — Score 9.1 (CRITICAL)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NAttack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityNone
Affected & Patched Versions
- Haxx Curl >= 8.17.0 and < 8.21.0
- Haxx Curl 8.21.0
What to do
Prioritize this fix. Exploit code is public, so attacks can follow quickly.
- Check whether you run Haxx Curl and which version.
- Update to a patched version listed above, then confirm the new version.
- Review logs and exposed services for signs of earlier compromise.
Timeline
- Jul 3, 2026Published
- Jul 7, 2026Record last modified
Score, severity and exploitation changes are tracked from the day Watchtower started logging them.
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External References
Data last checked: Nov 15, 2026 03:31 UTC