Deep Chat through 2.5.1 XSS via Markdown Link Validation Bypass
Summary
| CVE | CVE-2026-108852 |
|---|---|
| State | PUBLISHED |
| Assigner | VulnCheck |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-11 14:17:04 UTC |
| Updated | 2026-10-16 19:18:44 UTC |
| Description | Deep Chat through 2.5.1 contains a cross-site scripting vulnerability that allows attackers to inject javascript: links because RemarkableConfig.createNew disables Remarkable link validation. Attackers can place crafted Markdown links in AI responses, addMessage content, or loaded history to execute script in the embedding page when victims click them. |
Risk And Classification
Primary CVSS: v4.0 2.1 LOW from [email protected]
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/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
EPSS: 0.001850000 probability, percentile 0.075270000 (date 2026-10-16)
Problem Types: CWE-79 | CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 2.1 | LOW | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 2.1 | LOW | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N |
| 3.1 | [email protected] | Secondary | 4.7 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N |
| 3.1 | CNA | CVSS | 4.7 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
PresentPrivileges Required
NoneUser Interaction
ActiveConfidentiality
NoneIntegrity
NoneAvailability
NoneSub Conf.
LowSub Integrity
LowSub Availability
NoneCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/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
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
RequiredScope
ChangedConfidentiality
LowIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | OvidijusParsiunas | Deep Chat | affected 1.4.7 2.5.1 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.vulncheck.com/advisories/deep-chat-through-2.5.1-xss-via-markdown-link-vali... | [email protected] | www.vulncheck.com | |
| github.com/OvidijusParsiunas/deep-chat | [email protected] | github.com | |
| hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/ovidijusparsiunas-deep-chat-markdown-... | [email protected] | hackmd.io | |
| github.com/OvidijusParsiunas/deep-chat/blob/2.5.1/component/src/views/ch... | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: hieuPenguinnn (en)
There are currently no legacy QID mappings associated with this CVE.