# CVE-2026-113601: Memos missing authorization in ActivityService API methods

Source: https://junglewise.ai/threats/cve-2026-113601-memos-before-0-27-0-contains-a-missing-authorization  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-20. Updated: 2026-10-20  
License: CC BY 4.0 with a link back

CVE-2026-113601 · Severity: medium · CVSS 4.3 · Published 2026-10-20

Memos is a note-taking application that stores personal memos and activity records. The ActivityService API methods lack proper access controls, allowing any authenticated user to view all users' activity records and enumerate their private memos, creator IDs, and timestamps. An attacker can systematically discover what other users are doing and which memos they've accessed or modified.

Technologies: [Usememos Memos](https://junglewise.ai/threats/technologies/memos). Vendors: [Usememos](https://junglewise.ai/threats/vendors/usememos).

## Quick answers

**Is CVE-2026-113601 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-113601 being exploited in the wild.

**How severe is CVE-2026-113601?** Medium severity, with a CVSS score of 4.3, published 20 October 2026.

**Which products and versions are affected?** Usememos Memos before 0.27.0.

**Is there a fix for CVE-2026-113601?** Yes: fixed in 0.27.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-113601 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-113601?** Check whether you run Usememos Memos 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.

## How to fix

- Fixed in 0.27.0

## Technical details

The ListActivities and GetActivity API methods in ActivityService fail to enforce authorization checks before returning activity data. An authenticated attacker can enumerate sequential activity IDs to retrieve records belonging to other users, including references to private memos and activity metadata. The vulnerability requires authentication but allows privilege escalation to view unauthorized user activity.

## Affected products

- usememos Memos before 0.27.0

## Timeline

- 2026-10-20: disclosed

## References

- [https://github.com/usememos/memos/blob/v0.26.2/server/router/api/v1/activity_service.go](https://github.com/usememos/memos/blob/v0.26.2/server/router/api/v1/activity_service.go)
- [https://github.com/usememos/memos/commit/04f239a2fc74f7090c779a6a7b8a08238fd31b88](https://github.com/usememos/memos/commit/04f239a2fc74f7090c779a6a7b8a08238fd31b88)

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