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CVE-2026-6276 (GCVE-0-2026-6276)

Vulnerability from cvelistv5 – Published: 2026-05-13 08:28 – Updated: 2026-09-15 06:03
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.
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-13 17:24 UTC
CWE
  • CWE-346 - Origin Validation Error
Impacted products
Vendor Product Version CPE status
curl curl Affected: 7.71.0 , < 8.14.2 (semver)
Affected: 8.15.0 , < 8.16.1 (semver)
Affected: 8.17.0 , < 8.20.0 (semver)
guessed Create a notification for this product.
curl curl Affected: e15e51384a423be31318b3c9c7d612a1aae661fd , < 3a19987a87f393d9394fe5acc7643f6c263c92db (git)
guessed Create a notification for this product.
curl curl Affected: 8.19.0
Affected: 8.18.0
Affected: 8.17.0
Affected: 8.16.0
Affected: 8.15.0
Affected: 8.14.1
Affected: 8.14.0
Affected: 8.13.0
Affected: 8.12.1
Affected: 8.12.0
Affected: 8.11.1
Affected: 8.11.0
Affected: 8.10.1
Affected: 8.10.0
Affected: 8.9.1
Affected: 8.9.0
Affected: 8.8.0
Affected: 8.7.1
Affected: 8.7.0
Affected: 8.6.0
Affected: 8.5.0
Affected: 8.4.0
Affected: 8.3.0
Affected: 8.2.1
Affected: 8.2.0
Affected: 8.1.2
Affected: 8.1.1
Affected: 8.1.0
Affected: 8.0.1
Affected: 8.0.0
Affected: 7.88.1
Affected: 7.88.0
Affected: 7.87.0
Affected: 7.86.0
Affected: 7.85.0
Affected: 7.84.0
Affected: 7.83.1
Affected: 7.83.0
Affected: 7.82.0
Affected: 7.81.0
Affected: 7.80.0
Affected: 7.79.1
Affected: 7.79.0
Affected: 7.78.0
Affected: 7.77.0
Affected: 7.76.1
Affected: 7.76.0
Affected: 7.75.0
Affected: 7.74.0
Affected: 7.73.0
Affected: 7.72.0
Affected: 7.71.1
Affected: 7.71.0
guessed Create a notification for this product.
Show details on NVD website

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        "state": "PUBLISHED"
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    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

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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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


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