Findings

Vulnerability · CVE-2025-4035

A flaw was found in libsoup.

Published Apr 29, 2025 · corrected/updated Jun 30, 2026 · Red Hat Red Hat Enterprise Linux 10 · evidence confidence high

A flaw was found in libsoup. When handling cookies, libsoup clients mistakenly allow cookies to be set for public suffix domains if the domain contains at least two components and includes an uppercase character. This bypasses public suffix protections and could allow a malicious website to set cookies for domains it does not own, potentially leading to integrity issues such as session fixation.

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2025-4035 is a medium public vulnerability record for Red Hat Red Hat Enterprise Linux 10. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether Red Hat Red Hat Enterprise Linux 10 is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: Red Hat Red Hat Enterprise Linux 10 patch: 0:3.6.5-3.el10_0.6 (patch: 0:3.6.5-3.el10_0.6). Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: CVSS 4.3, EPSS 44.0%. It is not currently listed in the CISA Known Exploited catalog. Sources contributing to this record: cve_org, euvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

  • Exploitation evidence

    Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.

  • Patch and remediation

    No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Apr 29, 2025 · EUVD

    Detected

    A flaw was found in libsoup. When handling cookies, libsoup clients mistakenly allow cookies to be set for public suffix domains if the domain contains at least two components and includes an uppercase character. This bypasses public suffix protections and could allow a malicious website to set cookies for domains it does not own, potentially leading to integrity issues such as session fixation.

  2. Jun 30, 2026 · EUVD

    Updated

    A flaw was found in libsoup. When handling cookies, libsoup clients mistakenly allow cookies to be set for public suffix domains if the domain contains at least two components and includes an uppercase character. This bypasses public suffix protections and could allow a malicious website to set cookies for domains it does not own, potentially leading to integrity issues such as session fixation.

Affected

  • vendor Red Hat Red Hat Enterprise Linux 10 patch: 0:3.6.5-3.el10_0.6patch: 0:3.6.5-3.el10_0.6

Sources

  • CVE.orgVulnerability recordCVE-2025-4035

    Official CVE identifier

    cve.org
  • EUVDVulnerability recordEUVD-2025-15014

    A flaw was found in libsoup. When handling cookies, libsoup clients mistakenly allow cookies to be set for public suffix domains if the domain contains at least two components and includes an uppercase character. This bypasses public suffix protections and could allow a malicious

    euvd.enisa.europa.eu

References