EUVD-2026-37882
GHSA-mxqw-8v8m-qpmf
Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
PR:L for required forum account, UI:R for victim page-load, S:C for stored XSS executing cross-user in browser origin, C:L/I:L for session and content impact.
Primary rating from Vendor (CERT-PL).
CVSS VectorVendor: CERT-PL
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Lifecycle Timeline
1DescriptionCVE.org
UBB.threads is vulnerable to Stored XSS via user posts and user profile fields. The application fails to properly sanitize user input, allowing low privileged attackers to inject arbitrary JavaScript that executes in a victim's browser upon viewing.
Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 7.7.5 but may also affect other versions.
AnalysisAI
Stored XSS in UBB.threads 7.7.5 permits low-privileged forum members to permanently inject arbitrary JavaScript into post content and user profile fields, which then executes silently in any visitor's browser upon viewing the affected page. The vulnerability was discovered and disclosed by CERT-PL after unsuccessful vendor contact attempts, leaving remediation status unresolved. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires the attacker to possess a valid, low-privileged user account on the UBB.threads installation (PR:L), which grants access to post creation and profile editing - both standard features of a default forum deployment. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 4.0 score of 5.1 (Medium) is well-calibrated for this vulnerability class. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker registers a low-privileged account on the target UBB.threads forum and submits a post or updates their user profile to include a JavaScript payload such as a cookie-exfiltration script. When a forum administrator or other logged-in user subsequently views that post or profile page, the script executes in their browser under the forum's origin, silently transmitting their session token to an attacker-controlled endpoint. |
| Remediation | No vendor-released patch has been identified at time of analysis, as vendor contact was unsuccessful during CERT-PL's coordinated disclosure process. … Detailed patch versions, workarounds, and compensating controls in full report. |
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External POC / Exploit Code
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