CVE-2026-6276
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Using libcurl, when a custom Host: header is first set for an HTTP request
and a second request is subsequently done using the same easy handle but
without the custom Host: header set, the second request would use stale
information and pass on cookies meant for the first host in the second
request. Leak them.
Affected Software
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| curl | curl | 8.19.0 <= 8.19.0 | affected |
| curl | curl | 8.18.0 <= 8.18.0 | affected |
| curl | curl | 8.17.0 <= 8.17.0 | affected |
| curl | curl | 8.16.0 <= 8.16.0 | affected |
| curl | curl | 8.15.0 <= 8.15.0 | affected |
| curl | curl | 8.14.1 <= 8.14.1 | affected |
| curl | curl | 8.14.0 <= 8.14.0 | affected |
| curl | curl | 8.13.0 <= 8.13.0 | affected |
| curl | curl | 8.12.1 <= 8.12.1 | affected |
| curl | curl | 8.12.0 <= 8.12.0 | affected |
| curl | curl | 8.11.1 <= 8.11.1 | affected |
| curl | curl | 8.11.0 <= 8.11.0 | affected |
| curl | curl | 8.10.1 <= 8.10.1 | affected |
| curl | curl | 8.10.0 <= 8.10.0 | affected |
| curl | curl | 8.9.1 <= 8.9.1 | affected |
| curl | curl | 8.9.0 <= 8.9.0 | affected |
| curl | curl | 8.8.0 <= 8.8.0 | affected |
| curl | curl | 8.7.1 <= 8.7.1 | affected |
| curl | curl | 8.7.0 <= 8.7.0 | affected |
| curl | curl | 8.6.0 <= 8.6.0 | affected |
| curl | curl | 8.5.0 <= 8.5.0 | affected |
| curl | curl | 8.4.0 <= 8.4.0 | affected |
| curl | curl | 8.3.0 <= 8.3.0 | affected |
| curl | curl | 8.2.1 <= 8.2.1 | affected |
| curl | curl | 8.2.0 <= 8.2.0 | affected |
| curl | curl | 8.1.2 <= 8.1.2 | affected |
| curl | curl | 8.1.1 <= 8.1.1 | affected |
| curl | curl | 8.1.0 <= 8.1.0 | affected |
| curl | curl | 8.0.1 <= 8.0.1 | affected |
| curl | curl | 8.0.0 <= 8.0.0 | affected |
| curl | curl | 7.88.1 <= 7.88.1 | affected |
| curl | curl | 7.88.0 <= 7.88.0 | affected |
| curl | curl | 7.87.0 <= 7.87.0 | affected |
| curl | curl | 7.86.0 <= 7.86.0 | affected |
| curl | curl | 7.85.0 <= 7.85.0 | affected |
| curl | curl | 7.84.0 <= 7.84.0 | affected |
| curl | curl | 7.83.1 <= 7.83.1 | affected |
| curl | curl | 7.83.0 <= 7.83.0 | affected |
| curl | curl | 7.82.0 <= 7.82.0 | affected |
| curl | curl | 7.81.0 <= 7.81.0 | affected |
| curl | curl | 7.80.0 <= 7.80.0 | affected |
| curl | curl | 7.79.1 <= 7.79.1 | affected |
| curl | curl | 7.79.0 <= 7.79.0 | affected |
| curl | curl | 7.78.0 <= 7.78.0 | affected |
| curl | curl | 7.77.0 <= 7.77.0 | affected |
| curl | curl | 7.76.1 <= 7.76.1 | affected |
| curl | curl | 7.76.0 <= 7.76.0 | affected |
| curl | curl | 7.75.0 <= 7.75.0 | affected |
| curl | curl | 7.74.0 <= 7.74.0 | affected |
| curl | curl | 7.73.0 <= 7.73.0 | affected |
| curl | curl | 7.72.0 <= 7.72.0 | affected |
| curl | curl | 7.71.1 <= 7.71.1 | affected |
| curl | curl | 7.71.0 <= 7.71.0 | affected |
Weaknesses
- CWE-346 Origin Validation Error
ADP Enrichment
CVE Program Container
Additional References
CISA ADP Vulnrichment
- SSVC:
- Exploitation: poc
- Automatable: yes
- Technical Impact: partial
Additional References
References
- https://curl.se/docs/CVE-2026-6276.json
- https://curl.se/docs/CVE-2026-6276.html
- https://hackerone.com/reports/3671818
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