---
title: "CVE-2026-28474: Nextcloud Talk allowlist bypass via actor.name display name spoofing"
url: https://erroneo.us/security/cve/CVE-2026-28474/
description: "CVE-2026-28474 (@openclaw/nextcloud-talk (npm)): OpenClaw's Nextcloud Talk plugin versions prior to 2026.2.6 accept equality matching on the mutable…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-03-05
date_modified: 2026-09-17
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-28474"
kev: false
cvss: 9.3
epss: 0.00878
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-28474: Nextcloud Talk allowlist bypass via actor.name display name spoofing

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.9% , percentile 59: FIRST’s model estimates a 0.9% chance of exploitation activity in the next 30 days, higher than 59% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes @openclaw/nextcloud-talk (npm) <= 2026.2.2, fixed in 2026.2.6 . Check your lockfile, including transitive dependencies.

## What it is

OpenClaw's Nextcloud Talk plugin versions prior to 2026.2.6 accept equality matching on the mutable actor.name display name field for allowlist validation, allowing attackers to bypass DM and room allowlists. An attacker can change their Nextcloud display name to match an allowlisted user ID and gain unauthorized access to restricted conversations.

## Affected packages

- npm `@openclaw/nextcloud-talk` <= 2026.2.2 → fixed: 2026.2.6

## Affected products (CVE record)

- OpenClaw nextcloud-talk: < 2026.2.6

## Severity

- VulnCheck CVSS 4.0: 9.3 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`
- VulnCheck CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 4.0: 9.3 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.88% probability of exploitation activity in the next 30 days; percentile 59.

## Sources

- [GitHub Security Advisory (GHSA-r5h9-vjqc-hq3r)](https://github.com/openclaw/openclaw/security/advisories/GHSA-r5h9-vjqc-hq3r)
- [Patch Commit #1](https://github.com/openclaw/openclaw/commit/6b4b6049b47c3329a7014509594647826669892d)
- [GitHub Advisory GHSA-r5h9-vjqc-hq3r](https://github.com/advisories/GHSA-r5h9-vjqc-hq3r)
- [CVE.org record CVE-2026-28474](https://www.cve.org/CVERecord?id=CVE-2026-28474)
- [NVD entry CVE-2026-28474](https://nvd.nist.gov/vuln/detail/CVE-2026-28474)
- [VulnCheck Advisory: OpenClaw Nextcloud Talk < 2026.2.6 - Allowlist Bypass via actor.name Display Name Spoofing](https://www.vulncheck.com/advisories/openclaw-nextcloud-talk-allowlist-bypass-via-actorname-display-name-spoofing)
- [github.com](https://github.com/openclaw/openclaw/commit/660f87278c9f292061e097441e0b10c20d62b31b)
- [github.com](https://github.com/openclaw/openclaw/releases/tag/v2026.2.3)

---
Source page: https://erroneo.us/security/cve/CVE-2026-28474/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt