Is CVE-2026-21618 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-21618 being exploited in the wild.

How severe is CVE-2026-21618?

Medium severity, with a CVSS score of 6.1, published 19 January 2026.

Which products and versions are affected?

Hex (Hex) from 617e44c71f1dd9043870205f371d375c5c4d886d before c692438684ead90c3bcbfb9ccf4e63c768c668a8.

Is there a fix for CVE-2026-21618?

A patch was published on 2026-01-19: Fix merged in commit c692438684ead90c3bcbfb9ccf4e63c768c668a8 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-21618 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-21618?

Check whether you run Hex (Hex) or hexpm (Hex) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-21618: hexpm hexpm Cross-Site Scripting in OAuth Authorization View

CVE-2026-21618 · Severity: medium · CVSS 6.1 · Published 2026-01-19

A vulnerability exists in the Hex package manager's web interface, specifically within the OAuth and device authorization screens. This flaw could allow an attacker to execute malicious scripts in a user's browser if they are tricked into viewing a specially crafted page. Such an attack could lead to unauthorized actions being performed on behalf of the user or the theft of sensitive session information.

Technologies: Hex (Hex). Vendors: Hex.

Quick answers

Is CVE-2026-21618 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-21618 being exploited in the wild.
How severe is CVE-2026-21618?: Medium severity, with a CVSS score of 6.1, published 19 January 2026.
Which products and versions are affected?: Hex (Hex) from 617e44c71f1dd9043870205f371d375c5c4d886d before c692438684ead90c3bcbfb9ccf4e63c768c668a8.
Is there a fix for CVE-2026-21618?: A patch was published on 2026-01-19: Fix merged in commit c692438684ead90c3bcbfb9ccf4e63c768c668a8 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-21618 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-21618?: Check whether you run Hex (Hex) or hexpm (Hex) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A stored and reflected Cross-Site Scripting (XSS) vulnerability exists in the 'Elixir.HexpmWeb.SharedAuthorizationView' module of hexpm. The root cause is the use of raw() string interpolation instead of proper HTML escaping within the render_grouped_scopes/3 routine in lib/hexpm_web/views/shared_authorization_view.ex. An attacker can provide malicious JavaScript within OAuth scope names or descriptions which are then rendered without neutralization on the authorization screen. This requires a victim to interact with the authorization page. The issue has been patched by converting string interpolations to HEEx templates and implementing double-escaping for user-agent strings in Bootstrap popovers.

Affected products

hexpm hexpm from 617e44c71f1dd9043870205f371d375c5c4d886d before c692438684ead90c3bcbfb9ccf4e63c768c668a8
hexpm hex.pm from 2025-10-01 before 2026-01-19

Timeline

2026-01-19: advisory: Initial disclosure and NVD publication
2026-01-19: patched: Fix merged in commit c692438684ead90c3bcbfb9ccf4e63c768c668a8

References

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