How severe is CVE-2026-40043?

CVE-2026-40043 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-40043 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-40043?

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

Does CVE-2026-40043 have an EU (EUVD) identifier?

Yes. CVE-2026-40043 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22051.

When was CVE-2026-40043 published?

CVE-2026-40043 was published on 2026-04-13 and last updated on 2026-06-17.

CVE-2026-40043

CVE-2026-40043 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-639.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 7.1
EPSS exploit prediction: 0% (22nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22051
Weakness: CWE-639
Published: 2026-04-13
Last modified: 2026-06-17

Description

Pachno 1.0.6 contains an authentication bypass vulnerability in the runSwitchUser() action that allows authenticated low-privilege users to escalate privileges by manipulating the original_username cookie. Attackers can set the client-controlled original_username cookie to any value and request a switch to user ID 1 to obtain session tokens or password hashes belonging to administrator accounts.

Frequently asked questions

What is CVE-2026-40043?: Pachno 1.0.6 contains an authentication bypass vulnerability in the runSwitchUser() action that allows authenticated low-privilege users to escalate privileges by manipulating the original_username cookie. Attackers can set the client-controlled original_username cookie to any value and request a switch to user ID 1 to obtain session tokens or password hashes belonging to administrator accounts.
How severe is CVE-2026-40043?: CVE-2026-40043 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-40043 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-40043?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-40043 have an EU (EUVD) identifier?: Yes. CVE-2026-40043 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22051.
When was CVE-2026-40043 published?: CVE-2026-40043 was published on 2026-04-13 and last updated on 2026-06-17.

References

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