Pachno 1.0.6 return_to authentication bypass

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k1.18

Summaryinfo

A vulnerability was found in Pachno 1.0.6. It has been classified as problematic. This impacts an unknown function. Performing a manipulation of the argument return_to results in authentication bypass. This vulnerability is identified as CVE-2026-40039. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in Pachno 1.0.6. This affects an unknown code block. The manipulation of the argument return_to with an unknown input leads to a authentication bypass vulnerability. CWE is classifying the issue as CWE-305. The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error. This is going to have an impact on confidentiality. The summary by CVE is:

Pachno 1.0.6 contains an open redirection vulnerability that allows attackers to redirect users to arbitrary external websites by manipulating the return_to parameter. Attackers can craft malicious login URLs with unvalidated return_to values to conduct phishing attacks and steal user credentials.

The weakness was released by Gjoko Krstic as ZSL-2026-5981. The advisory is shared at zeroscience.mk. This vulnerability is uniquely identified as CVE-2026-40039 since 04/08/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/13/2026).

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

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Authentication bypass
CWE: CWE-305 / CWE-287
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/08/2026 CVE reserved
04/13/2026 +5 days Advisory disclosed
04/13/2026 +0 days VulDB entry created
04/13/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: ZSL-2026-5981
Researcher: Gjoko Krstic
Status: Not defined

CVE: CVE-2026-40039 (🔒)
GCVE (CVE): GCVE-0-2026-40039
GCVE (VulDB): GCVE-100-357201

Entryinfo

Created: 04/13/2026 21:40
Changes: 04/13/2026 21:40 (74)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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