Pomerium exposed OAuth2 access and ID tokens in user info endpoint response (CVE-2024-39315) | HOL Guard CVE

Medium · CVSS 5.7CVE-2024-39315GHSA-RRQR-7W59-637V

Pomerium exposed OAuth2 access and ID tokens in user info endpoint response

Answer in brief

CVE-2024-39315 records a Medium severity (CVSS 5.7) vulnerability in Pomerium exposed OAuth2 access and ID tokens in user info endpoint response. The current sources do not mark it as known exploited. The current feed maps github.com/pomerium/pomerium (go). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jul 5, 2024Updated Sep 10, 2026Source checked Sep 10, 2026First seen by HOL Aug 7, 2026Material review Sep 10, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 5.7
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 5.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps github.com/pomerium/pomerium (go). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
github.com/pomerium/pomeriumgo	>=0 <0.26.1	0.26.1

Recommended response

Check inventory. Check lockfiles and deployed manifests for github.com/pomerium/pomerium.
Review the reported fix. Update github.com/pomerium/pomerium to 0.26.1 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jul 5, 2024
Evidence: source:osv:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:record
First seen by HOL
Aug 7, 2026

Sources and claim methodology

Upstream source description

### Impact The Pomerium user info page (at `/.pomerium`) unintentionally included serialized OAuth2 access and ID tokens from the logged-in user's session. These tokens are not intended to be exposed to end users. This issue may be more severe in the presence of an XSS vulnerability in an upstream application proxied through Pomerium. If an attacker could insert a malicious script onto a web page proxied through Pomerium, that script could access these tokens by making a request to the `/.pomerium` endpoint. Upstream applications that authenticate only the ID token may be vulnerable to user impersonation using a token obtained in this manner. Note that an OAuth2 access token or ID token by itself is not sufficient to hijack a user's Pomerium session. Upstream applications should not be vulnerable to user impersonation via these tokens provided: - the application verifies the [Pomerium JWT](https://www.pomerium.com/docs/capabilities/getting-users-identity) for each request, - the connection between Pomerium and the application is secured by mTLS, - or the connection between Pomerium and the application is otherwise secured at the network layer. ### Patches Patched in Pomerium v0.26.1. ### Workarounds None ### For more information If you have any questions or comments about this advisory: - Open an issue in [pomerium/pomerium](https://github.com/pomerium/pomerium/issues) - Email us at [[email protected]](mailto:[email protected]) Credit to Vadim Sheydaev, aka Enr1g for reporting this issue.

Quoted source text, attributed separately from HOL analysis.