Out-of-bounds ReadWeakness · CWE-125

CVE-2025-4969

MEDIUM · 6.5 CVSS v3.1 Published 2025-05-21
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
74/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability was found in the libsoup package. This flaw stems from its failure to correctly verify the termination of multipart HTTP messages. This can allow a remote attacker to send a specially crafted multipart HTTP body, causing the libsoup-consuming server to read beyond its allocated memory boundaries (out-of-bounds read).

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A memory safety vulnerability exists in libsoup's multipart HTTP message parser. The library fails to properly verify message termination boundaries, allowing a remote attacker to send specially crafted multipart HTTP bodies that cause the server to read beyond allocated memory buffers (out-of-bounds read). This occurs during parsing of the multipart/form-data or similar multipart content types.

MitigationUpdate libsoup to the latest patched version that includes proper boundary termination verification. If patching is not immediately possible, implement request size limits and validate multipart message structure at a proxy or application layer before reaching libsoup.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
Low

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if libsoup is installed
    Check for libsoup library files on the system (common paths include /usr/lib/, /usr/local/lib/, or via package manager: dpkg -l | grep libsoup, rpm -qa | grep libsoup)
    Affected if libsoup library is present on the system
  2. Determine installed libsoup version
    Run 'pkg-config --modversion libsoup-3.0' or 'pkg-config --modversion libsoup-2.4' depending on the version found, or check via package manager
    Affected if the installed version has not yet received the boundary termination verification fix (compare against the latest patched release)
  3. Verify if applications use libsoup for HTTP handling
    Review application dependencies or configuration to confirm libsoup is used for handling HTTP requests (check application documentation, ldd output on binaries, or runtime dependencies)
    Affected if applications or services rely on libsoup to handle incoming HTTP requests
  4. Confirm if multipart content types are processed
    Check if the server or application accepts multipart/form-data, multipart/mixed, or similar multipart content types in HTTP requests (inspect configuration files, web server settings, or API endpoints)
    Affected if the environment processes multipart HTTP body content through libsoup
  5. Check for application-layer validation before libsoup
    Inspect if there is a proxy, WAF, or application-layer validation that validates multipart message structure and enforces request size limits before content reaches libsoup
    Affected if no intermediate validation layer exists and multipart content goes directly to libsoup for parsing

The environment is affected if libsoup is used to parse multipart HTTP content without additional validation or a patched version.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update libsoup to the latest patched version that includes proper boundary termination verification. If patching is not immediately possible, implement request size limits and validate multipart message structure at a proxy or application layer before reaching libsoup.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing5.0 h
  • Review / QA3.0 h
17.0 hours of engineering $2,970
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-4969 in production — separate from our analysis above.

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What this is

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What belongs here
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