CVE-2025-66635VulnerabilityPublished 16 Dec 2025Updated 22 Dec 2025

CVE-2025-66635: SEIKO EPSON Web Config · Stack-based buffer overflow

Affects SEIKO EPSON Web ConfigSource CVE Database V5

Not known to be exploited · CVSS 7.2 High.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.0 base score

7.2High

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

EPSS: 0.5% chance of exploitation in 30 days – higher than 44% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

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

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: High: The attacker is authorized with (i.e., requires) privileges that provide significant (e.g., administrative) control over the vulnerable component that could affect component-wide settings and files.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
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: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 16 Dec 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

AI-suggested

1. Immediately consult SEIKO EPSON CORPORATION's official advisories to identify affected versions and apply vendor-provided patches or updates as soon as they become available. 2. Restrict network access to the Web Config interface by implementing network segmentation and firewall rules limiting access to trusted administrators only. 3. Enforce strong authentication mechanisms and regularly audit user privileges to minimize the risk of credential compromise or misuse. 4. Monitor logs and network traffic for unusual activities related to Web Config, such as unexpected input patterns or unauthorized access attempts. 5. Consider deploying application-layer firewalls or intrusion prevention systems that can detect and block buffer overflow attack patterns targeting Web Config. 6. Educate administrators about the risks of this vulnerability and ensure they follow secure configuration and operational best practices. 7. If patching is delayed, temporarily disable or limit the use of Web Config interfaces where feasible to reduce exposure. 8. Maintain an incident response plan tailored to potential exploitation scenarios involving device management interfaces.

Description

Stack-based buffer overflow vulnerability exists in SEIKO EPSON Web Config. Specially crafted data input by a logged-in user may execute arbitrary code. As for the details of the affected products and versions, see the information provided by the vendor under [References].

Impact

For European organizations, the impact of CVE-2025-66635 can be substantial, especially in sectors relying heavily on Epson devices managed via Web Config, such as manufacturing, healthcare, and public administration. Successful exploitation could lead to unauthorized code execution, allowing attackers to manipulate device configurations, disrupt services, or use compromised devices as footholds for lateral movement within corporate networks. This threatens the confidentiality of sensitive information, the integrity of device configurations, and the availability of critical services. Given the high privileges required, insider threats or compromised credentials could accelerate exploitation. Additionally, organizations with regulatory obligations under GDPR must consider the potential data breach implications. The absence of known exploits in the wild provides a window for proactive mitigation, but the high severity score underscores the urgency of addressing this vulnerability to prevent future attacks.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 23 Dec 2025, 07:52 UTC

Technical details

References

Community reviews

Related threats