2.3
LOW CVSS 4.0
CVE-2026-75554
Explicit organization scopes survive token refresh after membership ends
Description

Insufficient Session Expiration vulnerability in the OAuth token refresh grant in hexpm hexpm allows a user removed from an organization to keep reading its private packages. expand_repositories_scope/3 in lib/hexpm/permissions.ex only rewrites the literal repositories scope, so an explicitly granted repository:<org> or docs:<org> scope passes through it untouched. The refresh grant re-derives a new token from the stored granted_scopes, which holds that expanded form, so every refresh reproduces the organization scope without revisiting membership. Because both CDN edges authorize repository access from the token claim without querying the database, an account removed from an organization retains read access for as long as it keeps refreshing, bounded by the 30 day refresh token lifetime rather than the 30 minute access token lifetime. This issue affects hex.pm: from 2025-10-10 before 2026-08-24.

INFO

Published Date :

Aug. 24, 2026, 9:17 p.m.

Last Modified :

Aug. 24, 2026, 9:17 p.m.

Remotely Exploit :

Yes !

Source :

6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Affected Products

The following products are affected by CVE-2026-75554 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 4.0 LOW 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
CVSS 4.0 LOW 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Solution
Fix session expiration for OAuth token refresh grant to prevent unauthorized access to private packages.
  • Re-evaluate user membership on token refresh.
  • Invalidate tokens upon user removal.
  • Update the `expand_repositories_scope/3` function.
  • Enforce token claims against database.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-75554.

URL Resource
https://cna.erlef.org/cves/CVE-2026-75554.html
https://github.com/hexpm/hexpm/commit/50cffd206490c49c92d7b63c8505949682abedb0
https://github.com/hexpm/hexpm/security/advisories/GHSA-24ww-j3f4-p49c
https://osv.dev/vulnerability/EEF-CVE-2026-75554
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-75554 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-2026-75554 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-2026-75554 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-75554 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.

  • New CVE Received by 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

    Aug. 24, 2026

    Action Type Old Value New Value
    Added Affected [{'cpes': ['cpe:2.3:a:hexpm:hexpm:*:*:*:*:*:*:*:*'], 'vendor': 'hexpm', 'modules': ["'Elixir.Hexpm.Permissions'", "'Elixir.Hexpm.OAuth.Tokens'", "'Elixir.HexpmWeb.API.OAuthController'"], 'product': 'hexpm', 'versions': [{'status': 'affected', 'version': '2025-10-10', 'lessThan': '2026-08-24', 'versionType': 'date'}], 'packageName': 'hex.pm', 'programFiles': ['lib/hexpm/permissions.ex', 'lib/hexpm/oauth/tokens.ex', 'lib/hexpm_web/controllers/api/oauth_controller.ex'], 'collectionURL': 'https://hex.pm', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': "'Elixir.Hexpm.Permissions':expand_repositories_scope/2"}, {'name': "'Elixir.Hexpm.OAuth.Tokens':create_for_user/6"}, {'name': "'Elixir.HexpmWeb.API.OAuthController':handle_refresh_token_grant/2"}]}, {'cpes': ['cpe:2.3:a:hexpm:hexpm:*:*:*:*:*:*:*:*'], 'repo': 'https://github.com/hexpm/hexpm', 'vendor': 'hexpm', 'modules': ["'Elixir.Hexpm.Permissions'", "'Elixir.Hexpm.OAuth.Tokens'", "'Elixir.HexpmWeb.API.OAuthController'"], 'product': 'hexpm', 'versions': [{'status': 'affected', 'version': '650faa03af511e74c1b3b49ec12d35666b6984c4', 'lessThan': '50cffd206490c49c92d7b63c8505949682abedb0', 'versionType': 'git'}], 'packageURL': 'pkg:github/hexpm/hexpm', 'packageName': 'hexpm/hexpm', 'programFiles': ['lib/hexpm/permissions.ex', 'lib/hexpm/oauth/tokens.ex', 'lib/hexpm_web/controllers/api/oauth_controller.ex'], 'collectionURL': 'https://github.com', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': "'Elixir.Hexpm.Permissions':expand_repositories_scope/2"}, {'name': "'Elixir.Hexpm.OAuth.Tokens':create_for_user/6"}, {'name': "'Elixir.HexpmWeb.API.OAuthController':handle_refresh_token_grant/2"}]}]
    Added Description Insufficient Session Expiration vulnerability in the OAuth token refresh grant in hexpm hexpm allows a user removed from an organization to keep reading its private packages. expand_repositories_scope/3 in lib/hexpm/permissions.ex only rewrites the literal repositories scope, so an explicitly granted repository:<org> or docs:<org> scope passes through it untouched. The refresh grant re-derives a new token from the stored granted_scopes, which holds that expanded form, so every refresh reproduces the organization scope without revisiting membership. Because both CDN edges authorize repository access from the token claim without querying the database, an account removed from an organization retains read access for as long as it keeps refreshing, bounded by the 30 day refresh token lifetime rather than the 30 minute access token lifetime. This issue affects hex.pm: from 2025-10-10 before 2026-08-24.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/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 CWE CWE-613
    Added Reference https://cna.erlef.org/cves/CVE-2026-75554.html
    Added Reference https://github.com/hexpm/hexpm/commit/50cffd206490c49c92d7b63c8505949682abedb0
    Added Reference https://github.com/hexpm/hexpm/security/advisories/GHSA-24ww-j3f4-p49c
    Added Reference https://osv.dev/vulnerability/EEF-CVE-2026-75554
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.