Mattermost doesn't authenticate Atlassian Connect installed callbacks, allowing a remote unauthenticated attacker to inject a rogue sharedSecret
CVSS score
6.4
EPSS probability
%0.3
Risk score
0.0
Published
3 mo ago
Etkilenen ürün ve sürüm için yayımlanan güvenlik güncellemesini uygulayın.
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Vulnerability description
DayBreach CVE AI Research
CVE-2026-6673 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.
Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to authenticate Atlassian Connect installed callbacks, allowing a remote unauthenticated attacker to inject a rogue sharedSecret and disrupt the Jira integration via POST to /ac/installed during the pending-install window.. Mattermost Advisory ID: MMSA-2026-00654
IMPACT: Affected Products and Software
Affected Products
The following products are affected by CVE-2026-6673 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.
RED HAT CSAF/VEX: Product Impact Check
SCORING: CVSS from Multiple Sources
CVSS Scores
The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.
| SCORE | VERSION | SEVERITY | VECTOR | SOURCE |
|---|---|---|---|---|
| 6.4 | CVSS 3.x | — | Vector not published | GitHub Advisory |
| 0.0 | CVSS 4.0 | — | Vector not published | GitHub Advisory |
Patch and Remediation Guide
Solution & Remediation Advisory
4 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.
10.11.18+incompatibleOSV düzeltilmiş sürüm: 10.11.18+incompatible
11.5.6+incompatibleOSV düzeltilmiş sürüm: 11.5.6+incompatible
11.6.3+incompatibleOSV düzeltilmiş sürüm: 11.6.3+incompatible
11.7.1+incompatibleOSV düzeltilmiş sürüm: 11.7.1+incompatible
Public exploit and active exploitation status
Verified exploit intelligence
CVE-2026-6673 : the database holds 2 public PoC/exploit sources for it. For direct links to the sources, open the Public Exploits tab.
Weakness Classification and Attack Patterns (CWE & CAPEC)
CWE - Common Weakness Enumeration
While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-6673 is associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-6673 weaknesses.
Attack Vector and Accessibility
Official Sources and Advisories
Similar Vulnerabilities
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