CVE-2019-1126
CVE-2019-1126 is a medium-severity vulnerability in Microsoft Windows Server 2012 with a CVSS 3.x base score of 5.3. 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-307.
Key facts
- Severity: Medium (CVSS 3.x base score 5.3)
- CVSS v2: 5.0
- EPSS exploit prediction: 5% (91st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-307
- Affected product: Microsoft Windows Server 2012
- Published:
- Last modified:
Description
A security feature bypass vulnerability exists in Active Directory Federation Services (ADFS) which could allow an attacker to bypass the extranet lockout policy.To exploit this vulnerability, an attacker could run a specially crafted application, which would allow an attacker to launch a password brute-force attack or cause account lockouts in Active Directory.This security update corrects how ADFS handles external authentication requests., aka 'ADFS Security Feature Bypass Vulnerability'. This CVE ID is unique from CVE-2019-0975.
Frequently asked questions
- What is CVE-2019-1126?
- A security feature bypass vulnerability exists in Active Directory Federation Services (ADFS) which could allow an attacker to bypass the extranet lockout policy.To exploit this vulnerability, an attacker could run a specially crafted application, which would allow an attacker to launch a password brute-force attack or cause account lockouts in Active Directory.This security update corrects how ADFS handles external authentication requests., aka 'ADFS Security Feature Bypass Vulnerability'. This CVE ID is unique from CVE-2019-0975.
- How severe is CVE-2019-1126?
- CVE-2019-1126 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
- Is CVE-2019-1126 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-1126?
- CVE-2019-1126 primarily affects Microsoft Windows Server 2012. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2019-1126?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2019-1126 published?
- CVE-2019-1126 was published on 2019-07-15 and last updated on 2026-06-17.
References
Affected products (5)
- cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2016:1803:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2016:1903:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*
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