Varnish Cache up to 7.6.1 HTTP1 Request request smuggling

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability was found in Varnish Cache up to 7.6.1. It has been rated as problematic. This impacts an unknown function of the component HTTP1 Request Handler. Performing a manipulation results in request smuggling. This vulnerability was named CVE-2025-30346. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic has been found in Varnish Cache up to 7.6.1. This affects an unknown function of the component HTTP1 Request Handler. The manipulation with an unknown input leads to a request smuggling vulnerability. CWE is classifying the issue as CWE-444. The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Varnish Cache before 7.6.2 and Varnish Enterprise before 6.0.13r10 allow client-side desync via HTTP/1 requests.

The advisory is shared at varnish-cache.org. This vulnerability is uniquely identified as CVE-2025-30346 since 03/21/2025. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 233596 (Debian dla-4101 : libvarnishapi-dev - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 7.6.2 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (233596) and EUVD (EUVD-2025-7260). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 5.4
CNA Vector (MITRE): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Request smuggling
CWE: CWE-444
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 233596
Nessus Name: Debian dla-4101 : libvarnishapi-dev - security update

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Cache 7.6.2

Timelineinfo

03/21/2025 🔍
03/21/2025 +0 days 🔍
03/21/2025 +0 days 🔍
06/07/2025 +78 days 🔍

Sourcesinfo

Advisory: varnish-cache.org
Status: Confirmed

CVE: CVE-2025-30346 (🔍)
GCVE (CVE): GCVE-0-2025-30346
GCVE (VulDB): GCVE-100-300573
EUVD: 🔍

Entryinfo

Created: 03/21/2025 08:00
Updated: 06/07/2025 20:41
Changes: 03/21/2025 08:00 (63), 04/01/2025 12:27 (2), 06/07/2025 20:41 (1)
Complete: 🔍
Cache ID: 216:9F6:103

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