CVE-2026-25732VulnerabilityPublished 6 Feb 2026Updated 9 Feb 2026

CVE-2026-25732: zauberzeug nicegui · Path Traversal

Affects zauberzeug niceguiSource CVE Database V5

Not known to be exploited · public exploit available (Exploit-DB) · CVSS 7.5 High : upgrade to 3.7.0 as a priority.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

7.5High

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

EPSS: 3.4% chance of exploitation in 30 days – higher than 88% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 3.7.0

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

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

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: 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: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

t = 0 is the CVE’s publication on cve.org

Disclosed: evidence found.
CVE published 6 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
1 Exploit-DB entry, 83 days after disclosure
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

CVE ID reserved
by GitHub_M
2026-02-0516:48Z, 28 hours before disclosure
CVE published
on cve.org
2026-02-0621:09Z, t = 0
In Threat Radar
record ingested
2026-02-0621:30Z, 20 minutes after disclosure
First Exploit-DB entry (opens in a new tab)
NiceGUI 3.6.1 - Path Traversal
2026-04-30, 83 days after disclosure

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

Upgrade zauberzeug nicegui to 3.7.0.

Affected software

Product	Affected	Fixed in
zauberzeugnicegui	Affected <3.7.0	Fixed in 3.7.0
PyPInicegui`pkg:pypi/nicegui`Other threats	Affected <3.7.0	Fixed in 3.7.0

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

AI-suggested

European organizations should immediately upgrade all NiceGUI deployments to version 3.7.0 or later to ensure the vulnerability is patched. Where upgrading is not immediately feasible, developers must implement strict sanitization of all client-supplied filenames before incorporating them into filesystem paths. This includes removing or neutralizing directory traversal sequences such as '../' and restricting filenames to safe character sets. Additionally, adopting the use of generated or fixed filenames instead of client-supplied names can prevent exploitation. Implementing application-level controls such as sandboxing file upload directories, enforcing least privilege on file system permissions, and monitoring file system changes can further reduce risk. Security teams should audit existing applications for vulnerable usage patterns and conduct penetration testing to verify remediation. Finally, network-level protections like web application firewalls (WAFs) can be tuned to detect and block suspicious file upload requests containing traversal payloads.

Description

NiceGUI is a Python-based UI framework. Prior to 3.7.0, NiceGUI's FileUpload.name property exposes client-supplied filename metadata without sanitization, enabling path traversal when developers use the pattern UPLOAD_DIR / file.name. Malicious filenames containing ../ sequences allow attackers to write files outside intended directories, with potential for remote code execution through application file overwrites in vulnerable deployment patterns. This design creates a prevalent security footgun affecting applications following common community patterns. Note: Exploitation requires application code incorporating file.name into filesystem paths without sanitization. Applications using fixed paths, generated filenames, or explicit sanitization are not affected. This vulnerability is fixed in 3.7.0.

Impact

For European organizations, this vulnerability poses a serious risk to web applications built using NiceGUI versions prior to 3.7.0, especially those that handle file uploads without proper filename sanitization. Successful exploitation can lead to unauthorized file writes outside designated directories, enabling attackers to overwrite application files, inject malicious code, or disrupt application functionality. This can result in remote code execution, compromising the confidentiality and integrity of systems and data. Organizations in sectors with sensitive data or critical infrastructure are particularly at risk, as attackers could leverage this vulnerability to escalate privileges or establish persistent access. The impact extends to reputational damage, regulatory non-compliance (e.g., GDPR), and operational disruption. Given the vulnerability requires no authentication and no user interaction, the attack surface is broad, increasing the likelihood of exploitation if vulnerable applications are exposed to the internet.

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #6OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks…
Implementation · Input Validation
Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174).
OWASP Cheat Sheets
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V12.3.1 (opens in a new tab)
Attack patterns
Path Traversal (opens in a new tab)
Using Slashes and URL Encoding Combined to Bypass Validation Logic (opens in a new tab)
Manipulating Web Input to File System Calls (opens in a new tab)
Using Escaped Slashes in Alternate Encoding (opens in a new tab)
Using Slashes in Alternate Encoding (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

Timeline

What to do

Affected software

Description

AI analysisMachine-generated, updated 14 Feb 2026, 12:11 UTC

Public exploits and detection1 Exploit-DB entry

WeaknessesCWE-22

Technical details

References

Community reviews

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