CVE-2026-87862

high

Description

Importing a `includeSubDomains` parent HSTS entry before a longer-lived child entry, silently drops the child. Consequently, when the parent expires, the child's valid HSTS policy is lost, causing curl to issue unencrypted HTTP requests rather than upgrading to HTTPS.

References

https://hackerone.com/reports/3972357

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-105309

https://curl.se/docs/CVE-2026-87862.json

https://curl.se/docs/CVE-2026-87862.html

Details

Source: Mitre, NVD

Published: 2026-10-20

Updated: 2026-10-30

Risk Information

CVSS v2

Base Score: 7.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 8.1

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.00995