8.8
HIGH CVSS 4.0
CVE-2026-8890
code100x Mobile API Authentication Bypass via Header Spoofing
Description

code100x contains an authentication bypass vulnerability in the Mobile API that allows unauthenticated attackers to impersonate arbitrary users by supplying a crafted JSON payload in the 'g' HTTP header. The middleware in middleware.ts skips identity header generation when an Auth-Key header is present without validating its value, allowing attackers to inject a spoofed user identity header that the downstream route handler in the mobile courses endpoint accepts as trusted, granting unauthorized access to course data belonging to any enrolled user or administrator.

INFO

Published Date :

May 26, 2026, 7:16 p.m.

Last Modified :

May 26, 2026, 8:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-8890 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Fix authentication bypass by validating the Auth-Key header before identity generation.
  • Validate Auth-Key header presence and value.
  • Ensure identity header generation is secure.
  • Review downstream route handler trust.
  • Deploy the updated middleware and API.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-8890 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-8890 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-8890 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-8890 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    May. 26, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/code100x/cms/issues/1924
    Added Reference https://github.com/code100x/cms/pull/1927
  • New CVE Received by [email protected]

    May. 26, 2026

    Action Type Old Value New Value
    Added Description code100x contains an authentication bypass vulnerability in the Mobile API that allows unauthenticated attackers to impersonate arbitrary users by supplying a crafted JSON payload in the 'g' HTTP header. The middleware in middleware.ts skips identity header generation when an Auth-Key header is present without validating its value, allowing attackers to inject a spoofed user identity header that the downstream route handler in the mobile courses endpoint accepts as trusted, granting unauthorized access to course data belonging to any enrolled user or administrator.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
    Added CWE CWE-639
    Added Reference https://github.com/code100x/cms/issues/1924
    Added Reference https://github.com/code100x/cms/pull/1927
    Added Reference https://github.com/code100x/cms/pull/1927/changes/88c6c5e94e23da101235c4c7e9c7591ac1016549
    Added Reference https://github.com/code100x/cms/pull/1927/changes/90b489ee7c63c301107d6374d4b3f2b8e4060fe5
    Added Reference https://www.vulncheck.com/advisories/code100x-mobile-api-authentication-bypass-via-header-spoofing
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.