CVE-2025-9901
Libsoup: improper handling of http vary header in libsoup caching
Description
A flaw was found in libsoup’s caching mechanism, SoupCache, where the HTTP Vary header is ignored when evaluating cached responses. This header ensures that responses vary appropriately based on request headers such as language or authentication. Without this check, cached content can be incorrectly reused across different requests, potentially exposing sensitive user information. While the issue is unlikely to affect everyday desktop use, it could result in confidentiality breaches in proxy or multi-user environments.
INFO
Published Date :
Sept. 3, 2025, 1:15 p.m.
Last Modified :
Sept. 4, 2025, 3:36 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2025-9901
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE |
Solution
- Update libsoup to a version that correctly handles the Vary header.
- Ensure caching mechanisms respect the Vary header for varying responses.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-9901.
| URL | Resource |
|---|---|
| https://access.redhat.com/security/cve/CVE-2025-9901 | |
| https://bugzilla.redhat.com/show_bug.cgi?id=2392790 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-9901 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-9901
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-9901 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-9901 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Sep. 03, 2025
Action Type Old Value New Value Added Description A flaw was found in libsoup’s caching mechanism, SoupCache, where the HTTP Vary header is ignored when evaluating cached responses. This header ensures that responses vary appropriately based on request headers such as language or authentication. Without this check, cached content can be incorrectly reused across different requests, potentially exposing sensitive user information. While the issue is unlikely to affect everyday desktop use, it could result in confidentiality breaches in proxy or multi-user environments. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Added CWE CWE-524 Added Reference https://access.redhat.com/security/cve/CVE-2025-9901 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2392790