CVE-2021-25276
CVE-2021-25276 is a high-severity vulnerability in Solarwinds Serv-u with a CVSS 3.x base score of 7.1. 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-732.
Key facts
- Severity: High (CVSS 3.x base score 7.1)
- CVSS v2: 3.6
- EPSS exploit prediction: 0% (37th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-732
- Affected product: Solarwinds Serv-u
- Published:
- Last modified:
Description
In SolarWinds Serv-U before 15.2.2 Hotfix 1, there is a directory containing user profile files (that include users' password hashes) that is world readable and writable. An unprivileged Windows user (having access to the server's filesystem) can add an FTP user by copying a valid profile file to this directory. For example, if this profile sets up a user with a C:\ home directory, then the attacker obtains access to read or replace arbitrary files with LocalSystem privileges.
Frequently asked questions
- What is CVE-2021-25276?
- In SolarWinds Serv-U before 15.2.2 Hotfix 1, there is a directory containing user profile files (that include users' password hashes) that is world readable and writable. An unprivileged Windows user (having access to the server's filesystem) can add an FTP user by copying a valid profile file to this directory. For example, if this profile sets up a user with a C:\ home directory, then the attacker obtains access to read or replace arbitrary files with LocalSystem privileges.
- How severe is CVE-2021-25276?
- CVE-2021-25276 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
- Is CVE-2021-25276 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-25276?
- CVE-2021-25276 primarily affects Solarwinds Serv-u. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-25276?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-25276 published?
- CVE-2021-25276 was published on 2021-02-03 and last updated on 2026-06-17.
References
Affected products (2)
- cpe:2.3:a:solarwinds:serv-u:*:*:*:*:*:*:*:*
- cpe:2.3:a:solarwinds:serv-u:15.2.2:-:*:*:*:*:*:*
More vulnerabilities in Solarwinds Serv-u
- CVE-2020-35481 — Critical (CVSS 9.8): SolarWinds Serv-U before 15.2.2 allows Unauthenticated Macro Injection.
- CVE-2025-40541 — Critical (CVSS 9.1): An Insecure Direct Object Reference (IDOR) vulnerability exists in Serv-U, which when exploited, gives a malicious…
- CVE-2025-40540 — Critical (CVSS 9.1): A type confusion vulnerability exists in Serv-U which when exploited, gives a malicious actor the ability to execute…
- CVE-2025-40539 — Critical (CVSS 9.1): A type confusion vulnerability exists in Serv-U which when exploited, gives a malicious actor the ability to execute…
- CVE-2025-40538 — Critical (CVSS 9.1): A broken access control vulnerability exists in Serv-U which when exploited, gives a malicious actor the ability to…
- CVE-2025-40549 — Critical (CVSS 9.1): A Path Restriction Bypass vulnerability exists in Serv-U that when abused, could give a malicious actor with access to…
All CVEs affecting Solarwinds Serv-u →
Other CWE-732 (Incorrect Permission Assignment for Critical Resource) vulnerabilities
- CVE-2026-9508 — Critical (CVSS 10.0): Incorrect permission settings on a critical resource in Suprema BioStar 2 (versions 2.9.3 through 2.9.11) that allow…
- CVE-2025-14988 — Critical (CVSS 10.0): A security issue has been identified in ibaPDA that could allow unauthorized actions on the file system under certain…
- CVE-2025-69426 — Critical (CVSS 10.0): The Ruckus vRIoT IoT Controller firmware versions prior to 3.0.0.0 (GA) contain hardcoded credentials for an operating…
- CVE-2025-12004 — Critical (CVSS 10.0): Incorrect Permission Assignment for Critical Resource vulnerability in The Wikimedia Foundation Mediawiki - Lockdown…
- CVE-2014-125121 — Critical (CVSS 10.0): Array Networks vAPV (version 8.3.2.17) and vxAG (version 9.2.0.34) appliances are affected by a privilege escalation…
- CVE-2025-46093 — Critical (CVSS 9.9): LiquidFiles before 4.1.2 supports FTP SITE CHMOD for mode 6777 (setuid and setgid), which allows FTPDrop users to…
Browse all CWE-732 (Incorrect Permission Assignment for Critical Resource) vulnerabilities →