How severe is CVE-2026-40039?

CVE-2026-40039 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-40039 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-40039?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-40039 have an EU (EUVD) identifier?

Yes. CVE-2026-40039 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22043.

When was CVE-2026-40039 published?

CVE-2026-40039 was published on 2026-04-13 and last updated on 2026-06-17.

CVE-2026-40039

CVE-2026-40039 is a medium-severity vulnerability with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-305.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 7.1
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22043
Weakness: CWE-305
Published: 2026-04-13
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-40039?: 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.
How severe is CVE-2026-40039?: CVE-2026-40039 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-40039 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-40039?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-40039 have an EU (EUVD) identifier?: Yes. CVE-2026-40039 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22043.
When was CVE-2026-40039 published?: CVE-2026-40039 was published on 2026-04-13 and last updated on 2026-06-17.

References

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