CVE-2026-6276 (GCVE-0-2026-6276)
Vulnerability from cvelistv5 – Published: 2026-05-13 08:28 – Updated: 2026-05-13 17:26
VLAI?
Title
stale custom cookie host causes cookie leak
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.
Severity ?
7.5 (High)
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| curl | curl |
Affected:
8.19.0 , ≤ 8.19.0
(semver)
Affected: 8.18.0 , ≤ 8.18.0 (semver) Affected: 8.17.0 , ≤ 8.17.0 (semver) Affected: 8.16.0 , ≤ 8.16.0 (semver) Affected: 8.15.0 , ≤ 8.15.0 (semver) Affected: 8.14.1 , ≤ 8.14.1 (semver) Affected: 8.14.0 , ≤ 8.14.0 (semver) Affected: 8.13.0 , ≤ 8.13.0 (semver) Affected: 8.12.1 , ≤ 8.12.1 (semver) Affected: 8.12.0 , ≤ 8.12.0 (semver) Affected: 8.11.1 , ≤ 8.11.1 (semver) Affected: 8.11.0 , ≤ 8.11.0 (semver) Affected: 8.10.1 , ≤ 8.10.1 (semver) Affected: 8.10.0 , ≤ 8.10.0 (semver) Affected: 8.9.1 , ≤ 8.9.1 (semver) Affected: 8.9.0 , ≤ 8.9.0 (semver) Affected: 8.8.0 , ≤ 8.8.0 (semver) Affected: 8.7.1 , ≤ 8.7.1 (semver) Affected: 8.7.0 , ≤ 8.7.0 (semver) Affected: 8.6.0 , ≤ 8.6.0 (semver) Affected: 8.5.0 , ≤ 8.5.0 (semver) Affected: 8.4.0 , ≤ 8.4.0 (semver) Affected: 8.3.0 , ≤ 8.3.0 (semver) Affected: 8.2.1 , ≤ 8.2.1 (semver) Affected: 8.2.0 , ≤ 8.2.0 (semver) Affected: 8.1.2 , ≤ 8.1.2 (semver) Affected: 8.1.1 , ≤ 8.1.1 (semver) Affected: 8.1.0 , ≤ 8.1.0 (semver) Affected: 8.0.1 , ≤ 8.0.1 (semver) Affected: 8.0.0 , ≤ 8.0.0 (semver) Affected: 7.88.1 , ≤ 7.88.1 (semver) Affected: 7.88.0 , ≤ 7.88.0 (semver) Affected: 7.87.0 , ≤ 7.87.0 (semver) Affected: 7.86.0 , ≤ 7.86.0 (semver) Affected: 7.85.0 , ≤ 7.85.0 (semver) Affected: 7.84.0 , ≤ 7.84.0 (semver) Affected: 7.83.1 , ≤ 7.83.1 (semver) Affected: 7.83.0 , ≤ 7.83.0 (semver) Affected: 7.82.0 , ≤ 7.82.0 (semver) Affected: 7.81.0 , ≤ 7.81.0 (semver) Affected: 7.80.0 , ≤ 7.80.0 (semver) Affected: 7.79.1 , ≤ 7.79.1 (semver) Affected: 7.79.0 , ≤ 7.79.0 (semver) Affected: 7.78.0 , ≤ 7.78.0 (semver) Affected: 7.77.0 , ≤ 7.77.0 (semver) Affected: 7.76.1 , ≤ 7.76.1 (semver) Affected: 7.76.0 , ≤ 7.76.0 (semver) Affected: 7.75.0 , ≤ 7.75.0 (semver) Affected: 7.74.0 , ≤ 7.74.0 (semver) Affected: 7.73.0 , ≤ 7.73.0 (semver) Affected: 7.72.0 , ≤ 7.72.0 (semver) Affected: 7.71.1 , ≤ 7.71.1 (semver) Affected: 7.71.0 , ≤ 7.71.0 (semver) |
Credits
Muhamad Arga Reksapati
Daniel Stenberg
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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