CVE-2023-53934VulnerabilityPublished 18 Dec 2025

CVE-2023-53934: Kentico Xperience · Improper Neutralization of Server-Side Includes (SSI) Within a Web Page

Affects Kentico XperienceSource CVE Database V5

Not known to be exploited · CVSS 8.7 High.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 4.0 base score

8.7High

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 36% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: None
User Interaction: None
Vulnerable system confidentiality: None
Vulnerable system integrity: None
Vulnerable system availability: High
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

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

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, 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: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: High: There is a total loss of availability, resulting in the attacker being able to fully deny access to resources in the Vulnerable System; 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 Vulnerable System (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).
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 18 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 2026-10-26.

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
Kentico Xperience	Affected =0	Fixed in–

AI-suggested

1. Immediately restrict network access to the GetResource handler endpoint to trusted IP addresses or internal networks only, reducing exposure to external attackers. 2. Deploy and configure Web Application Firewalls (WAFs) with custom rules to detect and block suspicious or malformed requests targeting the GetResource handler, focusing on patterns indicative of SSI injection attempts. 3. Monitor web server logs and network traffic for unusual request patterns or spikes in traffic to the vulnerable endpoint, enabling early detection of exploitation attempts. 4. Engage with Kentico support or security advisories to obtain patches or updates as soon as they become available and apply them promptly. 5. If patching is not immediately possible, consider temporary measures such as disabling SSI processing for the affected handler or isolating vulnerable services behind reverse proxies with strict input validation. 6. Conduct internal security assessments and penetration testing focused on this vulnerability to understand exposure and validate mitigation effectiveness. 7. Educate development and operations teams about the risks of improper input validation and SSI-related vulnerabilities to prevent similar issues in custom code or integrations.

Description

CVE-2023-53934 is a high-severity denial of service (DoS) vulnerability in Kentico Xperience caused by improper neutralization of Server-Side Includes (SSI) within a web page. Attackers can exploit this flaw by sending specially crafted requests to the GetResource handler, which lacks proper input validation, leading to service disruption. The vulnerability requires no authentication or user interaction and can be exploited remotely over the network. Although no known exploits are currently reported in the wild, the CVSS score of 8.7 indicates a significant risk to availability. European organizations using Kentico Xperience for content management or digital experience platforms should prioritize patching or mitigating this vulnerability to maintain service continuity. Countries with high adoption of Kentico Xperience and critical digital infrastructure are at greater risk. Immediate mitigation steps include restricting access to the vulnerable handler, implementing web application firewall (WAF) rules to detect and block malicious requests, and monitoring for unusual traffic patterns targeting the GetResource endpoint.

Impact

The primary impact of CVE-2023-53934 is on the availability of services hosted on Kentico Xperience platforms. A successful exploitation can cause denial of service, disrupting access to websites or digital services, which can lead to operational downtime, loss of customer trust, and potential financial losses. For European organizations, especially those in sectors such as e-commerce, government, healthcare, and media that rely heavily on Kentico Xperience, this disruption could affect critical business functions and public-facing services. The vulnerability could also be leveraged as part of a larger attack campaign to degrade service availability during periods of heightened geopolitical tension or cyber conflict. Since the vulnerability does not affect confidentiality or integrity directly, the risk is primarily service disruption. However, prolonged outages could indirectly impact data availability and business continuity. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, as attackers may develop exploits rapidly once details are publicized.

Summary

CVE-2023-53934 is a vulnerability identified in Kentico Xperience, a widely used digital experience platform and content management system. The flaw arises from improper neutralization of Server-Side Includes (SSI) within web pages, specifically in the GetResource handler component. SSI is a server-side scripting language used to include dynamic content in web pages. Improper input validation in this context allows an attacker to craft malicious requests that exploit the SSI processing mechanism, causing the server to enter a state that disrupts normal service operations, resulting in a denial of service (DoS). The vulnerability is remotely exploitable without requiring authentication or user interaction, making it accessible to any attacker with network access to the affected server. The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N) reflects a network attack vector with low complexity and no privileges or user interaction needed, but with a high impact on availability. Although no public exploits have been reported yet, the vulnerability's nature and ease of exploitation make it a critical concern for organizations relying on Kentico Xperience for their web presence and digital services. The lack of patch links suggests that a fix may not yet be publicly available, emphasizing the need for interim mitigations.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Dec 2025, 21:11 UTC

Technical details

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