CVE-2026-103903 (GCVE-0-2026-103903)
Vulnerability from cvelistv5
Published
2026-10-12 10:37
Modified
2026-10-13 11:57
Severity ?
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
VLAI Severity ?
EPSS score ?
CWE
- CWE-863 - Incorrect Authorization
Summary
An incorrect authorization vulnerability in the WinBox
authentication flow of MikroTik RouterOS allows a remote authenticated attacker
with credentials for a low-privilege account permitted to use WinBox to obtain
the authorization policy of a different existing account. The stage-one EC-SRP
challenge and proof are verified using the attacker's account, while the
independently supplied stage-two username is used to install the target
account's privileges. By specifying a higher-privilege account such as admin, a
low-privilege user can obtain a full administrative session without knowing the
target account's password and can use that session to increase the privileges
of the attacker's own account.
References
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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