CVE-2025-63317Public exploitNetwork attack vector

Stored XSS via unsanitized inline SVG attachments

Published Dec 1, 2025 · Updated Dec 2, 2025

Stored XSS in Todoist 8896 allows remote authenticated users to execute JavaScript when another user opens an uploaded SVG attachment. The upload endpoint accepts SVG content without sanitization, then a signed CDN URL serves it as image/svg+xml with inline disposition and no CSP sandbox. An account and user interaction are required; the script runs in the attachment viewer's browser context and can read or modify data available to that session.

CVSS severity5.4
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Todoist 8896 allows remote authenticated users to execute JavaScript when another user opens an uploaded SVG attachment. The upload endpoint accepts SVG content without sanitization, then a signed CDN URL serves it as image/svg+xml with inline disposition and no CSP sandbox. An account and user interaction are required; the script runs in the attachment viewer's browser context and can read or modify data available to that session.

The record

CVE
CVE-2025-63317
Published
Dec 1, 2025
Updated
Dec 2, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 1, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 2, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.4CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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