CVE-2026-42393
The comparison used for the doveadm password and API key is not fully timing safe and can reveal the length of the configured secret. An attacker with access to the same network as the doveadm service, able to make repeated requests and measure response timing accurately, can learn the length of the secret, which reduces the effort needed to guess it. The secret value itself is not disclosed. Restrict network access to the doveadm service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.
What this means for your business
- An attacker can use it from inside the same network, without a login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 3.1 (v3.1)
- Vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N- Weakness
- CWE-200
- Assigned by
- security@open-xchange.com
Dates
- Published
- 2026-08-28
- Last modified
- 2026-09-03
- Sources
- NVD