What is the CVSS score of EUVD-2026-29343?

EUVD-2026-29343 has a CVSS 3.1 base score of 5.8 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:N/A:N. EPSS exploitation probability: 0.0%.

Is there a patch available for EUVD-2026-29343?

Yes, a patch is available for EUVD-2026-29343. Update the affected software to the latest version immediately.

Outline EUVD-2026-29343

| CVE-2026-44695 MEDIUM

Cross-Site Request Forgery (CSRF) (CWE-352)

2026-05-11 GitHub_M

CSRF Outline

5.8

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

5.8 MEDIUM

AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:N/A:N

vuln.today AI

5.8 MEDIUM

AC:H for prerequisite OAuth code acquisition; PR:L for attacker's required Slack account; S:C because the linked Slack identity impacts a component outside the callback; C:H for victim content searchability; I:N and A:N as no modification or disruption occurs.

3.1 AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:N/A:N

4.0 AV:N/AC:H/AT:N/PR:L/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Primary rating from GitHub Advisory.

CVSS VectorGitHub Advisory

Attack Vector

Network

Attack Complexity

High

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

None

Availability

None

Lifecycle Timeline

Analysis Generated

Jul 23, 2026 - 23:32 vuln.today

Patch available

May 11, 2026 - 23:03 EUVD

CVE Published

May 11, 2026 - 21:11 nvd

MEDIUM 5.8

DescriptionGitHub Advisory

Outline is a service that allows for collaborative documentation. Prior to 1.7.1, the Slack integration callback for GET /auth/slack.post accepts an unsigned, session-independent OAuth state value. A third party who can obtain a Slack OAuth code for the same Outline Slack client can make a logged-in Outline user complete the callback and link that user's Outline account to the attacker's Slack team_id and user_id. The linked Slack identity can then use the Slack /outline search command as the victim Outline user. This vulnerability is fixed in 1.7.1.

AnalysisAI

Outline's Slack integration callback endpoint (GET /auth/slack.post) in versions before 1.7.1 accepts an unsigned, session-independent OAuth state parameter, enabling an attacker to hijack the account-linking flow for any logged-in Outline user. By obtaining a valid Slack OAuth authorization code for the same Outline Slack app and delivering a crafted callback URL to a victim, the attacker silently links the victim's Outline account to the attacker's Slack team_id and user_id, granting ongoing ability to query the victim's private Outline content via the Slack /outline search command. SSVC confirms a proof of concept exists; however, EPSS stands at 0.01% and CISA KEV status is absent, indicating exploitation is not yet widespread.

Technical ContextAI

Outline is an open-source collaborative documentation platform that supports Slack OAuth for authentication and workspace integration. RFC 6749 (OAuth 2.0) requires the 'state' parameter to be an opaque, cryptographically unpredictable value bound to the user's session, functioning as a CSRF token to prevent cross-site request forgery during the OAuth handshake. The affected endpoint GET /auth/slack.post omits this validation entirely - the state value is neither signed nor session-tied - making it trivially forgeable. The root cause maps to CWE-352 (Cross-Site Request Forgery) applied to an OAuth callback flow, a variant sometimes called OAuth state parameter injection or CSRF-on-OAuth. Per CPE cpe:2.3:a:outline:outline:*:*:*:*:*:*:*:*, all versions of the Outline application prior to 1.7.1 carry this flaw wherever the Slack integration is configured.

RemediationAI

The vendor-released patch is Outline version 1.7.1, which resolves the vulnerability by binding the OAuth state parameter to the user's session and validating it on callback. Operators should upgrade to 1.7.1 immediately using the standard Outline update process; the advisory at https://github.com/outline/outline/security/advisories/GHSA-mjgw-5j7q-gv8v provides upgrade guidance. If immediate patching is not possible, disabling the Slack integration entirely eliminates the attack surface with no residual risk from this vulnerability - the trade-off is loss of Slack-based authentication and the /outline Slack search command for all users. WAF rules or rate limiting cannot reliably mitigate this flaw because the crafted callback uses legitimately issued OAuth codes and appears as a valid OAuth redirect.