VulnerabilityPublished 12 Aug 2025Updated 13 Feb 2026

CVE-2025-53138: Microsoft Windows Server 2008 R2 Service Pack 1 · Use of Uninitialized Resource

Affects Microsoft Windows Server 2008 R2 Service Pack 1Source CVE Database V5

Not known to be exploited · CVSS 5.7 Medium.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score

5.7Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 1.1% chance of exploitation in 30 days – higher than 67% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

Base metrics

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: Required
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Temporal metrics

Exploit Code Maturity: Unproven
Remediation Level: Official Fix
Report Confidence: Confirmed

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.
Exploit Code Maturity: Unproven: No exploit code is available, or an exploit is theoretical.
Remediation Level: Official Fix: A complete vendor solution is available. Either the vendor has issued an official patch, or an upgrade is available.
Report Confidence: Confirmed: Detailed reports exist, or functional reproduction is possible (functional exploits may provide this). Source code is available to independently verify the assertions of the research, or the author or vendor of the affected code has confirmed the presence of the vulnerability.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 12 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Microsoft Windows Server 2008 R2 Service Pack 1	Affected =6.1.7601.0	Fixed in–

AI-suggested

Apply any official patches or security updates released by Microsoft for Windows Server 2008 R2 SP1 RRAS as soon as they become available.
If patching is not feasible, disable the Routing and Remote Access Service if it is not essential to business operations.
Restrict network access to RRAS services using firewall rules, limiting exposure to trusted hosts and networks only.
Enforce strict access controls and monitoring on accounts authorized to use RRAS to reduce the risk of exploitation.
Implement network segmentation to isolate legacy servers running Windows Server 2008 R2 from sensitive or critical network segments.
Monitor network traffic for unusual or unauthorized RRAS activity that could indicate exploitation attempts.
Plan and prioritize migration from Windows Server 2008 R2 to supported versions to eliminate exposure to legacy vulnerabilities.
Educate administrators and users about the risks and ensure user interaction requirements are understood to prevent inadvertent exploitation.

Description

Use of uninitialized resource in Windows Routing and Remote Access Service (RRAS) allows an authorized attacker to disclose information over a network.

Impact

For European organizations, the impact of CVE-2025-53138 is primarily the potential unauthorized disclosure of sensitive information within networks using Windows Server 2008 R2 SP1 with RRAS enabled. This could compromise confidentiality of internal communications or network configurations, potentially aiding further attacks or espionage. Critical infrastructure sectors, government agencies, and enterprises relying on legacy Windows Server environments are at higher risk. The vulnerability does not allow direct system compromise or denial of service, but information leakage can facilitate lateral movement or targeted attacks. Since Windows Server 2008 R2 is an older platform, organizations that have not upgraded or migrated may face increased exposure. The requirement for authorized access and user interaction limits the attack surface but does not eliminate risk, especially in environments with many privileged users or remote access enabled. European organizations with compliance obligations under GDPR must consider the confidentiality breach implications and report incidents accordingly.

CWE-908Use of Uninitialized Resource (opens in a new tab)
Base weaknessLikelihood of exploit: Medium
The product uses or accesses a resource that has not been initialized.
Implementation
Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all required steps.
Implementation
Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.
Implementation
Avoid race conditions (CWE-362) during initialization routines.
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53138 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 14 Feb 2026, 10:44 UTC

WeaknessesCWE-908

Technical details

References

Community reviews

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