CVE-2026-0857
Use of a Password Hash With Insufficient Computational Effort in Mesalvo MEONA (MEONA Server and MEONA Client) for user accounts whose password was last set under a ve…
Published May 20, 2026 · corrected/updated Sep 25, 2026 · evidence confidence high
Use of a Password Hash With Insufficient Computational Effort in Mesalvo MEONA (MEONA Server and MEONA Client) for user accounts whose password was last set under a version before MEONA 2024.10. MEONA versions before 2024.10 protected stored passwords with SHA-1 (versions from October 2015) or stored them without protection (earlier versions). Since MEONA 2024.10 (June 2024) Argon2 is the default method and every password that is set or changed is stored with Argon2; passwords last set under an earlier version keep the earlier method until they are changed. An administrator could in addition select the storage method per account. A MEONA super administrator can read the stored value of such accounts in the user administration of the MEONA Client or export it through administrative database functions. Only accounts managed locally in MEONA are affected; accounts authenticated through the operating hospital's directory service (Active Directory / Entra ID) have no password stored in MEONA. In typical installations end users authenticate through the directory service and local accounts are limited to emergency and technical accounts. Exploitation requires super administrator permissions in MEONA (or direct access to the MEONA database) from within the operating hospital's network; MEONA is operated exclusively within closed hospital networks without exposure to the public Internet, and where a hospital permits remote access to that network at all, it is only through the hospital's own remote-access infrastructure (e.g. VPN) under the hospital's control. Installations in which every password has been set or changed under MEONA 2024.10 or later are not affected. Mesalvo is not aware of any exploitation outside the reported security test. This issue affects MEONA Server and MEONA Client in versions 2024.10, 2025.04 and 2026.03 (for accounts with passwords last set under earlier versions). MEONA 2025.04.24 and 2026.03.02 (planned Q4 2026) remove the legacy storage methods,
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2026-0857 is a medium public vulnerability record for this product. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether this product is in your estate, then compare installed versions with the affected ranges. Affected version ranges have not been ingested yet. Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 4.4, EPSS 0.1%. It is not currently listed in the CISA Known Exploited catalog. Weakness classes: CWE-916. Sources contributing to this record: cve_org, epss, nvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.
Patch and remediation
No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
May 20, 2026 · NIST NVD
Detected
Use of a Password Hash With Insufficient Computational Effort in Mesalvo MEONA (MEONA Server and MEONA Client) for user accounts whose password was last set under a version before MEONA 2024.10. MEONA versions before 2024.10 protected stored passwords with SHA-1 (versions from October 2015) or stored them without protection (earlier versions). Since MEONA 2024.10 (June 2024) Argon2 is the default
Sep 25, 2026 · NIST NVD
Updated
Use of a Password Hash With Insufficient Computational Effort in Mesalvo MEONA (MEONA Server and MEONA Client) for user accounts whose password was last set under a version before MEONA 2024.10. MEONA versions before 2024.10 protected stored passwords with SHA-1 (versions from October 2015) or stored them without protection (earlier versions). Since MEONA 2024.10 (June 2024) Argon2 is the default
Sources
- CVE.orgVulnerability recordCVE-2026-0857
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-0857
30-day exploitation probability 0.1%
first.org - NIST NVDVulnerability recordCVE-2026-0857
Use of a Password Hash With Insufficient Computational Effort in Mesalvo MEONA (MEONA Server and MEONA Client) for user accounts whose password was last set under a version before MEONA 2024.10. MEONA versions before 2024.10 protected stored passwords with SHA-1 (versions from Oc
nvd.nist.gov