CVE-2025-21618 | NiceGUI On Air authentication issue

NiceGUI is an easy-to-use, Python-based UI framework. Prior to 2.9.1, authenticating with NiceGUI logged in the user for all browsers, including browsers in incognito mode. This vulnerability is fixed in 2.9.1.

Published: 2025-01-06 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-21618 is rated Moderate Risk (40.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.37%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-21618

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.21% 0.37% +0.16%
2 2026-02-14 0.13% 0.21% +0.07%
3 2025-11-21 0.13%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-21618

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2025-21618

GitHub Security Advisory for CVE-2025-21618

GHSA-v6jv-p6r8-j78w · Severity: high · Ecosystem: pip — NiceGUI On Air authentication issue

Affected software / configurations for CVE-2025-21618

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-21618

cvelogic Threat Intelligence