Quick answers
- Is CVE-2026-103903 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-103903 being exploited in the wild.
- How severe is CVE-2026-103903?
- High severity, with a CVSS score of 8.8, published 12 October 2026.
- Which products and versions are affected?
- MikroTik RouterOS before 7.24.5.
- Is there a fix for CVE-2026-103903?
- Yes: fixed in RouterOS 7.24.5, 7.25rc1 and later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-103903 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-103903?
- Check whether you run MikroTik RouterOS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: RouterOS 7.24.5, 7.25rc1 and later
Technical details
An incorrect authorization vulnerability in the WinBox authentication flow decouples the verified account from the account whose privileges are granted. The EC-SRP stage-one challenge and proof are verified against the attacker's low-privilege account, but a stage-two username parameter is independently used to install the target account's authorization policy. A network-based authenticated attacker with low-privilege credentials can complete authentication as themselves, then inject a high-privilege username to obtain that account's full privileges without knowing its password.
Affected products
- MikroTik RouterOS before 7.24.5
Timeline
- 2026-09-22: disclosed
- 2026-10-12: patched: CVE-2026-103903 published; fixes available since 2026-09-22