November 15, 2026

CVE Watchtower

CVE-2026-8286Haxx Curl

NVDCVSS scored by 134c704f-9b21-4f2e-91b3-4a467353bcc0

Vulnerability Summary

A vulnerability exists where a new transfer that uses STARTTLS to upgrade the
connection might reuse an existing live connection even though the TLS
configuration mismatches so it should not.
Severity Level
HIGH(8.1)
Published Date
Jul 3, 2026
Last Modified
Jul 7, 2026
Exploitation Status
Public exploit available
EPSS Score (30-Day)
0.31%Probability
Root Weakness (CWE)
CWE-295 β†—
See the MITRE CWE entry for the full definition of this weakness.
CVSS v3.1 Base Metrics — Score 8.1 (HIGH)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityNone

Affected & Patched Versions

Affected Versions
  • Haxx Curl >= 7.30.0 and < 8.21.0
Patched Versions
  • Haxx Curl 8.21.0

What to do

Prioritize this fix. Exploit code is public, so attacks can follow quickly.

  1. Check whether you run Haxx Curl and which version.
  2. Update to a patched version listed above, then confirm the new version.
  3. 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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Related Coverage

External References

Data last checked: Nov 15, 2026 03:31 UTC