Varnish Cache/Enterprise HTTP1 Request request smuggling

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.4$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Varnish Cache and Enterprise. This affects an unknown part of the component HTTP1 Request Handler. The manipulation results in request smuggling. This vulnerability is reported as CVE-2025-47905. The attack can be launched remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Varnish Cache and Enterprise (affected version not known). Affected is some unknown functionality 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. CVE summarizes:

Varnish Cache before 7.6.3 and 7.7 before 7.7.1, and Varnish Enterprise before 6.0.13r14, allow client-side desync via HTTP/1 requests, because the product incorrectly permits CRLF to be skipped to delimit chunk boundaries.

The advisory is shared for download at varnish-cache.org. This vulnerability is traded as CVE-2025-47905 since 05/13/2025. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 237462 (Debian dla-4187 : libvarnishapi-dev - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (237462). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

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

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 237462
Nessus Name: Debian dla-4187 : libvarnishapi-dev - security update

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

05/13/2025 🔍
05/14/2025 +1 days 🔍
05/14/2025 +0 days 🔍
05/29/2025 +15 days 🔍

Sourcesinfo

Advisory: varnish-cache.org
Status: Confirmed

CVE: CVE-2025-47905 (🔍)
GCVE (CVE): GCVE-0-2025-47905
GCVE (VulDB): GCVE-100-308772

Entryinfo

Created: 05/14/2025 03:50
Updated: 05/29/2025 19:19
Changes: 05/14/2025 03:50 (63), 05/16/2025 10:43 (3), 05/16/2025 10:44 (1), 05/16/2025 12:51 (1), 05/29/2025 11:21 (1), 05/29/2025 19:19 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

Discussion

 Anonymous User (+0)
1 Year ago
As per the description, CVE-2025-47905 also affects Varnish Enterprise. Therefore, I kindly ask if you could consider the associated CPE 'varnish-software:varnish_enterprise' and add it accordingly."

Best Regards,
TEAM CERT
 VulDB Community Team1 Year ago
Thank you. Surprisingly, the associated product list of the CVE entry CVE-2025-47905 does not. But according to the vendor advisory it does. We have updated the entry.
 Anonymous User (+0)
1 Year ago
I have noticed that for CVE-2025-47905 you have added the CPE related to Varnish Enterprise, but not the official one provided by NVD NIST, which is 'varnish-software:varnish_enterprise'. In the past, this CPE was used for CVE-2025-30346. Could you kindly review your classification and add the official NVD NIST CPE?
Thank you in advance..
Best Regards,
TEAM CERT
 VulDB Community Team1 Year ago
The Varnish Cache CPEs in the official NIST dictionary are rather chaotic and contradictory. Indeed, it looks like the correct string for the Enterprise edition is varnish-software:varnish_enterprise: - We have updated the entry.

◂ PreviousOverviewNext ▸

Want to stay up to date on a daily basis?

Enable the mail alert feature now!