Google Go net-http-internal-http2-x-net-http2 request smuggling

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$5k-$25k1.12

Summaryinfo

A vulnerability labeled as problematic has been found in Google Go. This affects an unknown function of the component net-http-internal-http2-x-net-http2. The manipulation results in request smuggling. This vulnerability was named CVE-2026-78660. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in Google Go (the affected version unknown). It has been classified as problematic. Affected is an unknown part of the component net-http-internal-http2-x-net-http2. 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 integrity. CVE summarizes:

Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing. However, this makes it possible for our HTTP/2 implementation to forward responses containing such headers to an HTTP/1 client when acting as a reverse proxy. If the HTTP/1 client also does not behave strictly enough, this can result in response smuggling.

This vulnerability is traded as CVE-2026-78660 since 08/25/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 10/09/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-95425). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Vendor

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License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/25/2026 CVE reserved
10/08/2026 +44 days VulDB entry created
10/09/2026 +0 days Advisory disclosed
10/09/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: google.com

Status: Confirmed

CVE: CVE-2026-78660 (🔒)
GCVE (CVE): GCVE-0-2026-78660
GCVE (VulDB): GCVE-100-415698
EUVD: 🔒

Entryinfo

Created: 10/09/2026 01:08
Updated: 10/09/2026 02:28
Changes: 10/09/2026 01:08 (51), 10/09/2026 02:28 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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