CVE-2026-6276 (GCVE-0-2026-6276)
Vulnerability from cvelistv5
Published
2026-05-13 08:28
Modified
2026-05-13 17:26
Severity ?
VLAI Severity ?
EPSS score ?
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.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| curl | curl |
Version: 8.19.0 ≤ 8.19.0 Version: 8.18.0 ≤ 8.18.0 Version: 8.17.0 ≤ 8.17.0 Version: 8.16.0 ≤ 8.16.0 Version: 8.15.0 ≤ 8.15.0 Version: 8.14.1 ≤ 8.14.1 Version: 8.14.0 ≤ 8.14.0 Version: 8.13.0 ≤ 8.13.0 Version: 8.12.1 ≤ 8.12.1 Version: 8.12.0 ≤ 8.12.0 Version: 8.11.1 ≤ 8.11.1 Version: 8.11.0 ≤ 8.11.0 Version: 8.10.1 ≤ 8.10.1 Version: 8.10.0 ≤ 8.10.0 Version: 8.9.1 ≤ 8.9.1 Version: 8.9.0 ≤ 8.9.0 Version: 8.8.0 ≤ 8.8.0 Version: 8.7.1 ≤ 8.7.1 Version: 8.7.0 ≤ 8.7.0 Version: 8.6.0 ≤ 8.6.0 Version: 8.5.0 ≤ 8.5.0 Version: 8.4.0 ≤ 8.4.0 Version: 8.3.0 ≤ 8.3.0 Version: 8.2.1 ≤ 8.2.1 Version: 8.2.0 ≤ 8.2.0 Version: 8.1.2 ≤ 8.1.2 Version: 8.1.1 ≤ 8.1.1 Version: 8.1.0 ≤ 8.1.0 Version: 8.0.1 ≤ 8.0.1 Version: 8.0.0 ≤ 8.0.0 Version: 7.88.1 ≤ 7.88.1 Version: 7.88.0 ≤ 7.88.0 Version: 7.87.0 ≤ 7.87.0 Version: 7.86.0 ≤ 7.86.0 Version: 7.85.0 ≤ 7.85.0 Version: 7.84.0 ≤ 7.84.0 Version: 7.83.1 ≤ 7.83.1 Version: 7.83.0 ≤ 7.83.0 Version: 7.82.0 ≤ 7.82.0 Version: 7.81.0 ≤ 7.81.0 Version: 7.80.0 ≤ 7.80.0 Version: 7.79.1 ≤ 7.79.1 Version: 7.79.0 ≤ 7.79.0 Version: 7.78.0 ≤ 7.78.0 Version: 7.77.0 ≤ 7.77.0 Version: 7.76.1 ≤ 7.76.1 Version: 7.76.0 ≤ 7.76.0 Version: 7.75.0 ≤ 7.75.0 Version: 7.74.0 ≤ 7.74.0 Version: 7.73.0 ≤ 7.73.0 Version: 7.72.0 ≤ 7.72.0 Version: 7.71.1 ≤ 7.71.1 Version: 7.71.0 ≤ 7.71.0 |
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"value": "Using libcurl, when a custom `Host:` header is first set for an HTTP request\nand a second request is subsequently done using the same *easy handle* but\nwithout the custom `Host:` header set, the second request would use stale\ninformation and pass on cookies meant for the first host in the second\nrequest. Leak them."
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"title": "stale custom cookie host causes cookie leak"
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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