CVE-2026-70617Public exploitNetwork attack vector

Authenticated group-DM access via unchecked recipient addition

Published Aug 5, 2026 · Updated Aug 5, 2026

Missing authorization in Spacebar Server before commit dcfd910 allows remote authenticated users to access arbitrary group DMs. The PUT /channels/{channel_id}/recipients/{user_id} handler adds the requested recipient without verifying that the caller belongs to the loaded channel. Possession of an obtainable group-DM identifier is sufficient to join, read all message history, post messages, or force-add other users.

CVSS severity8.6
High
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Spacebar Server before commit dcfd910 allows remote authenticated users to access arbitrary group DMs. The PUT /channels/{channel_id}/recipients/{user_id} handler adds the requested recipient without verifying that the caller belongs to the loaded channel. Possession of an obtainable group-DM identifier is sufficient to join, read all message history, post messages, or force-add other users.

The record

CVE
CVE-2026-70617
Published
Aug 5, 2026
Updated
Aug 5, 2026
Vendor
Spacebar
Product
Spacebar Server
Classifications
CWE-862, T1213.005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=dcfd91035e3da42abf5f32d8d86a35219225b3d4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Spacebar · Spacebar Serverversion=0 <=dcfd91035e3da42abf5f32d8d86a35219225b3d4

Published CVSS scores

8.1GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
8.6VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
T1213.005Messaging Applications

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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