Security readout for executives and security teams
Plain-English summary
Libsoup can mishandle cookie domain checks when uppercase characters appear in a cookie domain. A malicious website could set cookies for a domain it does not own, weakening trust in cookies and potentially enabling session fixation. The impact is integrity-focused, requires user interaction, and is rated medium by the supplied CVSS data.
Executive priority
Treat this as a routine but real integrity issue. It is not a critical outage-risk vulnerability, but organizations should patch through normal Linux maintenance, prioritizing systems where cookie trust affects sessions, embedded browsers, or user authentication flows.
Technical view
The flaw is a CWE-178 case-sensitivity issue in libsoup cookie handling. Public suffix protections can be bypassed when the cookie domain has at least two components and includes uppercase characters. Provided Red Hat data lists libsoup/libsoup3 on RHEL 6, 7, 8, 9, and 10 as affected.
Likely exposure
Exposure is most likely on Red Hat Enterprise Linux systems running applications that use libsoup or libsoup3 to process cookies from untrusted web content. The supplied bundle identifies RHEL 6 through 10 packages, but does not provide a complete non-Red Hat affected-product list.
Exploitation context
The bundle does not show CISA KEV listing or cited evidence of active exploitation. Exploitation would require a user or client application to interact with malicious web content that can influence cookie handling. The expected security consequence is cookie integrity abuse, not direct code execution or availability loss.
Researcher notes
The key weakness is inconsistent case handling during cookie domain validation against public suffix protections. The provided evidence supports Red Hat package impact and the general libsoup behavior, but does not include exploit reports, complete fixed-version data, or a full upstream affected-version matrix.
Mitigation direction
- Review Red Hat advisory RHSA-2025:8128 for vendor-approved package remediation.
- Update affected libsoup or libsoup3 packages when vendor-fixed builds are available.
- Prioritize systems running web-facing, desktop, or embedded clients that process cookies.
- Check GNOME libsoup upstream issue 443 for project-level guidance.
- Avoid relying on unpublished workarounds not documented by the vendor.
Validation and detection
- Inventory RHEL 6 through 10 hosts for installed libsoup and libsoup3 packages.
- Compare installed package builds against Red Hat CVE and RHSA guidance.
- Identify applications that use libsoup to process cookies from untrusted sites.
- Confirm regression coverage for public suffix cookie rejection with uppercase domains.
- Track remediation status separately for legacy RHEL versions.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-178: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2025-4035 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N2.81.4redhatVulnerability scoring details
Base CVSS 3.1 score
4.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- Source timelineredhat
Made public.
- Source timelineredhat
Reported to Red Hat.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- RHSA-2025:8128CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2025-4035CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2362651CVE reference, redhat · issue-tracking, x_refsource_REDHAT
- https://gitlab.gnome.org/GNOME/libsoup/-/issues/443CVE reference, redhat
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Handling of Case Sensitivity
Improper Handling of Case Sensitivity represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.