Vulnerability-Lookup

CVE-2026-44695 (GCVE-0-2026-44695)

Vulnerability from cvelistv5 – Published: 2026-05-11 21:11 – Updated: 2026-05-12 13:30

Title

Outline: Slack OAuth state can link a victim Outline account to an attacker Slack identity

Summary

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.

Severity

5.8 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-12 13:30 UTC

CWE

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

Assigner

GitHub_M mitre root

References

1 reference

URL	Tags
https://github.com/outline/outline/security/advis…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version	CPE status
outline	outline	Affected: < 1.7.1	guessed

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-44695

Vulnerability from fkie_nvd - Published: 2026-05-11 22:22 - Updated: 2026-06-17 10:51

Severity

5.8 (Medium) - CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:N/A:N
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/outline/outline/security/advisories/GHSA-mjgw-5j7q-gv8v	Exploit, Vendor Advisory
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/outline/outline/security/advisories/GHSA-mjgw-5j7q-gv8v	Exploit, Vendor Advisory

Impacted products

	Vendor	Product	Version
	getoutline	outline	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "outline",
          "vendor": "outline",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.7.1"
            }
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    }
  ],
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          "negate": false,
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  ],
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  "descriptions": [
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    }
  ],
  "id": "CVE-2026-44695",
  "lastModified": "2026-06-17T10:51:14.550",
  "metrics": {
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          "confidentialityImpact": "HIGH",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.