CVE-2025-49670VulnerabilityPublished 8 Jul 2025Updated 26 Feb 2026

CVE-2025-49670: Microsoft Windows Server 2008 R2 Service Pack 1 · Heap-based Buffer Overflow

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

Not known to be exploited · CVSS 6.5 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

6.5Medium

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

EPSS: 1.0% chance of exploitation in 30 days – higher than 63% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/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: None
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: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
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 8 Jul 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 2026-10-25.

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 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

1. Disable the Windows Routing and Remote Access Service (RRAS) if it is not essential to business operations, thereby eliminating the attack surface. 2. Restrict network exposure of RRAS by implementing strict firewall rules to limit access only to trusted IP addresses and networks. 3. Employ network segmentation to isolate legacy Windows Server 2008 R2 systems from critical infrastructure and sensitive data stores. 4. Monitor network traffic and system logs for unusual activity related to RRAS, including unexpected connection attempts or anomalous user interactions. 5. Educate users on the risks of social engineering and phishing attacks that could trigger user interaction required for exploitation. 6. Plan and prioritize upgrading or migrating from Windows Server 2008 R2 to supported versions with ongoing security updates. 7. Apply any future patches or security updates from Microsoft promptly once available. 8. Use intrusion detection/prevention systems (IDS/IPS) with signatures targeting RRAS exploitation attempts. 9. Conduct regular vulnerability assessments and penetration testing focused on legacy systems and exposed services.

Description

Heap-based buffer overflow in Windows Routing and Remote Access Service (RRAS) allows an unauthorized attacker to execute code over a network.

Impact

The primary impact of CVE-2025-49670 is unauthorized remote code execution on affected Windows Server 2008 R2 systems running RRAS, potentially leading to data confidentiality breaches. Attackers exploiting this vulnerability could gain access to sensitive network routing information or other protected data handled by RRAS. Although the vulnerability does not affect system integrity or availability directly, successful exploitation could serve as a foothold for further lateral movement or privilege escalation within an organization’s network. Organizations relying on legacy Windows Server 2008 R2 for critical infrastructure or VPN services are particularly at risk. The requirement for user interaction somewhat limits automated exploitation, but social engineering or phishing could facilitate triggering the vulnerability. The lack of available patches increases the risk window until mitigations or updates are provided. Overall, this vulnerability poses a moderate threat to organizations worldwide, especially those with exposed RRAS services and insufficient network segmentation or monitoring.

CWE-122Heap-based Buffer Overflow (opens in a new tab)
Variant weaknessLikelihood of exploit: HighCWE Top 25 (2025): #16
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Pre-design: Use a language or compiler that performs automatic bounds checking.
Architecture and Design
Use an abstraction library to abstract away risky APIs. Not a complete solution.
Operation · Build and Compilation · Environment Hardening
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index…
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
Attack patterns
Forced Integer Overflow (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

msrc.microsoft.com/update-guide/vulnerability/CVE-2025-49670 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Feb 2026, 21:46 UTC

WeaknessesCWE-122

Technical details

References

Community reviews

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