Name: CVE-2026-80255: Insertion of Sensitive Information Into Sent Data
Creator: Rapid7
Published: 2026-09-06T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-80255, CWE-201, CVSS 7.5, EPSS 0.00478

A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the `Secure` attribute causes curl to store the cookie without its Secure flag. The cookie might then wrongfully be sent over plaintext HTTP on subsequent requests to the same host.

CVSS Details

CVSS 3.1 Base Score: 7.5
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alpine Linux	—	Upgrade curl	Sep 7, 2026	Sep 6, 2026
Ubuntu	—	Upgrade libcurl3-gnutls (Ubuntu Pro)Upgrade libcurl4Upgrade libcurl3-nssUpgrade libcurl3-gnutlsUpgrade libcurl4-openssl-devUpgrade libcurl3-nss (Ubuntu Pro)Upgrade libcurl4-nss-dev (Ubuntu Pro)Upgrade libcurl4 (Ubuntu Pro)Upgrade libcurl4-gnutls-dev (Ubuntu Pro)Upgrade libcurl4-nss-devUpgrade libcurl4-gnutls-devUpgrade libcurl3 (Ubuntu Pro)Upgrade libcurl4t64Upgrade libcurl3t64-gnutlsUpgrade libcurl4-openssl-dev (Ubuntu Pro)Upgrade curlUpgrade curl (Ubuntu Pro)	Sep 27, 2026	Sep 24, 2026
Vmware Photon_os	—	Use 'tdnf update' to upgrade all packages to the latest version.	Sep 24, 2026	Sep 6, 2026

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CVSS Details

Covered by Rapid7

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