Red Hat Security Advisory: varnish:6 security update
Varnish Cache is a high-performance HTTP accelerator. It stores web pages in memory so web servers don't have to create the same web page over and over again, giving the website a significant speed up. Security Fix(es): * varnish: request smuggling attacks (CVE-2025-47905) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
AI Analysis
Technical Summary
CVE-2025-47905 is a vulnerability in Varnish Cache related to request smuggling attacks. Varnish Cache accelerates HTTP traffic by caching web pages in memory. The vulnerability allows an attacker to perform request smuggling, which can interfere with the processing of HTTP requests. Red Hat Product Security has rated this update as Important and released a security advisory (RHSA-2025:8294) providing updated varnish:6 packages for Red Hat Enterprise Linux 8.8 Extended Update Support to remediate the issue.
Potential Impact
The vulnerability enables request smuggling attacks against Varnish Cache, potentially allowing attackers to interfere with HTTP request processing. This could lead to security issues such as bypassing security controls or causing unexpected behavior in web applications relying on Varnish. The severity is rated as high by the source data, indicating a significant security impact if exploited.
Mitigation Recommendations
Red Hat has released updated varnish:6 packages for Red Hat Enterprise Linux 8.8 Extended Update Support that fix this vulnerability. Users should apply the security update as detailed in the Red Hat advisory RHSA-2025:8294 and the referenced article https://access.redhat.com/articles/11258. Since this is an official fix, applying the update fully mitigates the vulnerability.
Red Hat Security Advisory: varnish:6 security update
Description
Varnish Cache is a high-performance HTTP accelerator. It stores web pages in memory so web servers don't have to create the same web page over and over again, giving the website a significant speed up. Security Fix(es): * varnish: request smuggling attacks (CVE-2025-47905) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-47905 is a vulnerability in Varnish Cache related to request smuggling attacks. Varnish Cache accelerates HTTP traffic by caching web pages in memory. The vulnerability allows an attacker to perform request smuggling, which can interfere with the processing of HTTP requests. Red Hat Product Security has rated this update as Important and released a security advisory (RHSA-2025:8294) providing updated varnish:6 packages for Red Hat Enterprise Linux 8.8 Extended Update Support to remediate the issue.
Potential Impact
The vulnerability enables request smuggling attacks against Varnish Cache, potentially allowing attackers to interfere with HTTP request processing. This could lead to security issues such as bypassing security controls or causing unexpected behavior in web applications relying on Varnish. The severity is rated as high by the source data, indicating a significant security impact if exploited.
Mitigation Recommendations
Red Hat has released updated varnish:6 packages for Red Hat Enterprise Linux 8.8 Extended Update Support that fix this vulnerability. Users should apply the security update as detailed in the Red Hat advisory RHSA-2025:8294 and the referenced article https://access.redhat.com/articles/11258. Since this is an official fix, applying the update fully mitigates the vulnerability.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:8550
- Cve Count
- 1
Threat ID: 6a3da1cf4853345fc1824436
Added to database: 06/25/2026, 21:46:55 UTC
Last enriched: 07/12/2026, 10:17:41 UTC
Last updated: 09/10/2026, 19:36:50 UTC
Views: 14
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