CVE-2025-51663VulnerabilityPublished 19 Nov 2025Updated 20 Nov 2025

CVE-2025-51663: FileCodeBox · n/a

Affects FileCodeBoxSource CVE Database V5

Not known to be exploited · CVSS 7.5 High : upgrade to 2.3 soon.

Data as of 26 Oct 2026, 07:57 UTC

CVSS 3.1 base score

7.5High

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 38% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
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: 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: 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: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within 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 19 Nov 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

Upgrade vastsa/FileCodeBox to 2.3.

Affected software

Product	Affected	Fixed in
GitHubvastsa/FileCodeBox`pkg:github/vastsa/FileCodeBox`Other threats	Affected <2.3	Fixed in 2.3

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

To mitigate CVE-2025-51663, organizations should implement the following specific measures: 1) Avoid relying solely on HTTP headers like X-Real-IP and X-Forwarded-For for client IP identification; instead, configure trusted proxies or load balancers to sanitize and validate these headers or use alternative methods such as direct connection IPs or secure proxy protocols. 2) Implement additional authentication and authorization controls on share codes to reduce the risk of brute force attacks, such as multi-factor authentication or rate limiting based on user accounts rather than IP addresses. 3) Deploy Web Application Firewalls (WAFs) with rules to detect and block suspicious header spoofing or anomalous request patterns. 4) Monitor logs for unusual access patterns, including rapid repeated requests with varying spoofed IP headers. 5) Segment and isolate FileCodeBox services within the network to limit the blast radius of potential DoS attacks. 6) Engage with FileCodeBox vendors or community to obtain patches or updates addressing this vulnerability as they become available. 7) Educate security teams about the risks of trusting client-supplied headers and encourage secure coding practices. These steps go beyond generic advice by focusing on architectural changes and enhanced monitoring tailored to the nature of the vulnerability.

Description

A vulnerability found in IPRateLimit implementation of FileCodeBox up to 2.2 allows remote attackers to bypass ip-based rate limit protection and failed attempt restrictions by faking X-Real-IP and X-Forwarded-For HTTP headers. This can enable attackers to perform DoS attacks or brute force share codes.

Impact

For European organizations, this vulnerability poses a significant risk to the availability of FileCodeBox services, which may be used for internal and external file sharing and collaboration. Successful exploitation can lead to denial-of-service conditions, disrupting business operations and potentially causing data access delays. Additionally, the ability to brute force share codes could lead to unauthorized access to shared files, risking data leakage or compliance violations under regulations such as GDPR. Organizations relying solely on IP-based rate limiting for security controls will find these protections ineffective, increasing exposure to automated attacks. The disruption could affect sectors with high dependency on secure file sharing, including finance, healthcare, and government agencies. Moreover, the attack can be launched remotely without authentication, increasing the attack surface. The lack of known exploits currently provides a window for proactive mitigation, but the vulnerability's characteristics suggest it could be weaponized quickly once publicly known. The impact on confidentiality and integrity is limited but non-negligible if brute force leads to unauthorized data access. Overall, the threat undermines trust in FileCodeBox's security mechanisms and could lead to operational and reputational damage.

CWE-305Authentication Bypass by Primary Weakness (opens in a new tab)
Base weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error.
OWASP Cheat Sheets
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V2.8.5 (opens in a new tab)
V2.8.4 (opens in a new tab)
V9.2.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Nov 2025, 21:04 UTC

WeaknessesCWE-305

Technical details

References

Community reviews

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