CVE-2026-103957 Server-side request forgery in the OAuth2 discovery handling in Loom for AWS
An authenticated attacker can exploit SSRF in AWS Loom to steal access tokens and access internal network resources via crafted discovery documents.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-103957?
CVE-2026-103957 is a high-severity server-side request forgery vulnerability in AWS loom, published on 2 Oct 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
Server-side request forgery in the OAuth2 discovery handling in Loom for AWS before 1.7.0 might allow an authenticated remote user to obtain the access token of another user of the deployment and to cause the application to issue requests to arbitrary internal network locations, via a crafted discovery document address supplied when registering a tool server or remote agent configured for delegated authentication.
To remediate this issue, users should upgrade to version 1.7.0 or later.
Which versions are affected by CVE-2026-103957?
How do I fix CVE-2026-103957?
No fix has been published for CVE-2026-103957 yet. Limit exposure of the affected software until one is available.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-103957 being exploited?
There is no known exploitation of CVE-2026-103957 in the wild and no public exploit code.
Sources
Also known as GHSA-jcxf-gpf4-58hm.