stale custom cookie host causes cookie leak (curl curl)

CVE-2026-6276
HIGH 7.5

At a glance

Source
NVD
EPSS
EPSS 0.29 % · percentile 22 ()
State
PUBLISHED
Published
Updated
Assigner
curl
NVD status
Modified

Description

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.

Weaknesses (CWE)

  • CWE-346 — Origin Validation Error
  • CWE-319 — Cleartext Transmission of Sensitive Information

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCISA-ADP
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HNVD · nvd@nist.gov (Primary)
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HNVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
curl · curlaffected 7.71.0 < 8.14.2 ; affected 8.15.0 < 8.16.1 ; affected 8.17.0 < 8.20.0
curl · curlaffected e15e51384a423be31318b3c9c7d612a1aae661fd < 3a19987a87f393d9394fe5acc7643f6c263c92db
curl · curlaffected 8.19.0 ; affected 8.18.0 ; affected 8.17.0 ; affected 8.16.0 ; affected 8.15.0 ; affected 8.14.1

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD