x-net up to 0.54.x on Go improper validation of unsafe equivalence in input

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.
7.3	$0-$5k	0.00

Summaryinfo

A vulnerability was found in x-net up to 0.54.x on Go. It has been declared as problematic. Affected is an unknown function. Such manipulation leads to improper validation of unsafe equivalence in input. This vulnerability is referenced as CVE-2026-39821. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in x-net up to 0.54.x on Go. It has been rated as problematic. Affected by this issue is some unknown processing. The manipulation with an unknown input leads to a improper validation of unsafe equivalence in input vulnerability. Using CWE to declare the problem leads to CWE-1289. The product receives an input value that is used as a resource identifier or other type of reference, but it does not validate or incorrectly validates that the input is equivalent to a potentially-unsafe value. Impacted is integrity. CVE summarizes:

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode("xn--example-.com") incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna package. For example, a program which performs privilege checks on the ASCII hostname may reject "example.com" but permit "xn--example-.com". If that program subsequently converts the ASCII hostname to Unicode, it will inadvertently permits access to the Unicode name "example.com".

This vulnerability is handled as CVE-2026-39821 since 04/07/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available.

The vulnerability scanner Nessus provides a plugin with the ID 321072 (openSUSE 16 Security Update : grafana (openSUSE-SU-2026:20940-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.55.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (321072), EUVD (EUVD-2026-31449) and CERT Bund (WID-SEC-2026-1653). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

• Amazon Linux 2
• Red Hat Enterprise Linux
• Fedora Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• IBM MQ
• Golang Go
• SUSE openSUSE
• Red Hat OpenShift

Productinfo

Name

• x-net

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17
• 0.18
• 0.19
• 0.20
• 0.21
• 0.22
• 0.23
• 0.24
• 0.25
• 0.26
• 0.27
• 0.28
• 0.29
• 0.30
• 0.31
• 0.32
• 0.33
• 0.34
• 0.35
• 0.36
• 0.37
• 0.38
• 0.39
• 0.40
• 0.41
• 0.42
• 0.43
• 0.44
• 0.45
• 0.46
• 0.47
• 0.48
• 0.49
• 0.50
• 0.51
• 0.52
• 0.53
• 0.54

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.4
VulDB Meta Temp Score: 7.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 9.6
ADP CISA Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

Exploitinginfo

Class: Improper validation of unsafe equivalence in input
CWE: CWE-1289 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 321072
Nessus Name: openSUSE 16 Security Update : grafana (openSUSE-SU-2026:20940-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: x-net 0.55.0

Timelineinfo

04/07/2026 CVE reserved
05/22/2026 +45 days Advisory disclosed
05/22/2026 +0 days VulDB entry created
07/08/2026 +47 days VulDB entry last update

Sourcesinfo

Status: Confirmed

CVE: CVE-2026-39821 (🔒)
GCVE (CVE): GCVE-0-2026-39821
GCVE (VulDB): GCVE-100-365210
EUVD: 🔒
CERT Bund: WID-SEC-2026-1653 - Golang Go-Module (Net, Image, Crypto: Mehrere Schwachstellen

Entryinfo

Created: 05/22/2026 18:00
Updated: 07/08/2026 04:03
Changes: 05/22/2026 18:00 (51), 05/23/2026 08:09 (7), 05/23/2026 09:00 (1), 06/01/2026 08:53 (11), 06/14/2026 21:04 (2), 06/17/2026 14:10 (1), 06/19/2026 12:12 (1), 07/05/2026 01:03 (1), 07/08/2026 04:03 (1)
Complete: 🔍
Cache ID: 216::103

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

Discussion

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