Security readout for executives and security teams
Plain-English summary
Libsoup, a GNOME HTTP library used by Linux applications, can leak memory when parsing a malformed quality-list header containing all-zero elements. Repeated exposure could exhaust memory in affected applications and cause service disruption. The evidence points to availability impact, not data theft or code execution.
Executive priority
Treat as a moderate availability risk. It is not presented as code execution or data exposure, but memory leaks can still disrupt business services if affected applications process malicious or malformed HTTP header input. Patch through normal security maintenance, accelerating for exposed or reliability-critical systems.
Technical view
The flaw is a memory leak in libsoup's soup_header_parse_quality_list() parsing path for quality-list elements with all zeroes. CVSS is 6.5 with network attack vector, low complexity, no privileges, user interaction required, and high availability impact. Red Hat lists affected libsoup packages across RHEL 8 and 9 streams; RHEL 10 libsoup3 is listed unaffected.
Likely exposure
Most relevant to Red Hat Enterprise Linux 8 and 9 systems or applications linked against affected libsoup packages that parse attacker-influenced HTTP headers. Exposure depends on whether a reachable application invokes the vulnerable parser on untrusted quality-list header input. RHEL 6 and 7 status is unknown in the supplied data.
Exploitation context
The bundle does not show CISA KEV listing or active exploitation. The CVSS vector indicates remote delivery is possible but requires user interaction. A successful attack would aim at memory growth and denial of service, not confidentiality or integrity compromise.
Researcher notes
Evidence is centered on Red Hat package impact and the GNOME libsoup issue. The vulnerable function and trigger condition are named, but the bundle does not provide exploit details, broad exploit telemetry, or non-Red Hat fixed version mapping. Avoid assuming every libsoup-using application is practically reachable.
Mitigation direction
- Apply the relevant Red Hat security advisory updates for affected RHEL streams.
- Prioritize internet-facing or user-driven applications that use libsoup for HTTP parsing.
- Check vendor guidance for non-Red Hat distributions or bundled libsoup copies.
- Use compensating monitoring for abnormal process memory growth until updates are applied.
Validation and detection
- Inventory installed libsoup or libsoup3 packages and map versions to affected RHEL streams.
- Identify services and desktop applications linked against libsoup on exposed systems.
- Confirm updated packages from the relevant RHSA are installed after remediation.
- Monitor affected applications for repeatable memory growth during suspicious header processing.
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-401: Exact CWE lookup
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Open ATT&CK lookupCVE-2025-46420 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
- 6.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
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:N/A:H2.83.6redhatVulnerability scoring details
Base CVSS 3.1 score
6.5MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
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-2025:4439CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:4440CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:4508CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:4538CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:4560CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:4568CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:4609CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:4624CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2025:7436CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2025-46420CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2361963CVE reference, redhat · issue-tracking, x_refsource_REDHAT
- https://gitlab.gnome.org/GNOME/libsoup/-/issues/438CVE 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.
Missing Release of Memory after Effective Lifetime
Missing Release of Memory after Effective Lifetime represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.