CVE-2026-28313: CWE-639 Authorization Bypass Through User-Controlled Key in SolarWinds Serv-U
SolarWinds Serv-U is affected by an insecure direct object reference (IDOR) vulnerability that can lead to SMTP hijacking leading to arbitrary account takeover. The impact is lower in Windows deployments.
AI Analysis
Technical Summary
SolarWinds Serv-U contains an authorization bypass vulnerability classified as CWE-639, caused by insecure direct object references that can be manipulated through user-controlled keys. Exploitation of this vulnerability can result in SMTP hijacking and arbitrary account takeover. The impact is noted to be less severe on Windows deployments. The vulnerability has been assigned CVE-2026-28313 with a CVSS v3.1 score of 9.1 (AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H). No vendor advisory or patch information is currently available.
Potential Impact
Successful exploitation can lead to complete compromise of user accounts via SMTP hijacking, resulting in confidentiality, integrity, and availability impacts rated as high. The vulnerability allows an attacker with high privileges to bypass authorization controls through user-controlled keys. The impact is reportedly lower on Windows deployments, but remains critical overall.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix or mitigation is provided by SolarWinds, monitor for updates and apply any recommended temporary controls from the vendor. Do not assume the vulnerability is mitigated without vendor confirmation.
CVE-2026-28313: CWE-639 Authorization Bypass Through User-Controlled Key in SolarWinds Serv-U
Description
SolarWinds Serv-U is affected by an insecure direct object reference (IDOR) vulnerability that can lead to SMTP hijacking leading to arbitrary account takeover. The impact is lower in Windows deployments.
CVSS v3.1
Score 9.1critical
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
SolarWinds Serv-U contains an authorization bypass vulnerability classified as CWE-639, caused by insecure direct object references that can be manipulated through user-controlled keys. Exploitation of this vulnerability can result in SMTP hijacking and arbitrary account takeover. The impact is noted to be less severe on Windows deployments. The vulnerability has been assigned CVE-2026-28313 with a CVSS v3.1 score of 9.1 (AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H). No vendor advisory or patch information is currently available.
Potential Impact
Successful exploitation can lead to complete compromise of user accounts via SMTP hijacking, resulting in confidentiality, integrity, and availability impacts rated as high. The vulnerability allows an attacker with high privileges to bypass authorization controls through user-controlled keys. The impact is reportedly lower on Windows deployments, but remains critical overall.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix or mitigation is provided by SolarWinds, monitor for updates and apply any recommended temporary controls from the vendor. Do not assume the vulnerability is mitigated without vendor confirmation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- SolarWinds
- Date Reserved
- 2026-02-26T14:28:17.158Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a5f96f22a4a8d59895fb2b9
Added to database: 07/21/2026, 15:57:38 UTC
Last enriched: 07/30/2026, 03:51:09 UTC
Last updated: 09/03/2026, 10:52:08 UTC
Views: 63
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