PatchSiren cyber security CVE debrief
CVE-2021-47969 Exploit Db CVE debrief
CVE-2021-47969 is a high-severity denial-of-service issue in Color Notes 1.4. The supplied description says an attacker can crash the application by pasting excessively long character strings into note fields; the example payload is 350,000 repeated characters pasted twice into a new note, which can cause the app to stop responding. The supplied NVD metadata classifies the issue as network-reachable, low-complexity, no-privileges, no-user-interaction, and availability-impacting only. The supplied timeline records the CVE as published and modified on 2026-05-16T16:16:22.170Z.
- Vendor
- Exploit Db
- Product
- Unknown
- CVSS
- HIGH 8.7
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-05-16
- Original CVE updated
- 2026-05-16
- Advisory published
- 2026-05-16
- Advisory updated
- 2026-05-16
Who should care
Administrators and users running Color Notes 1.4, especially where untrusted text can be pasted into notes or where application availability is important.
Technical summary
The vulnerability is described as a denial of service caused by oversized pasted input in note fields. The supplied weakness mapping is CWE-789, and the CVSS v4 vector indicates AV:N/AC:L/AT:N/PR:N/UI:N with high availability impact and no confidentiality or integrity impact. In practical terms, the application can be forced into a non-responsive state through crafted input length rather than authentication or complex interaction.
Defensive priority
High. Because the supplied vector shows no privileges and no user interaction are required, and the impact is application availability, organizations should treat this as a priority if Color Notes 1.4 is present on systems that must remain responsive.
Recommended defensive actions
- Identify any systems running Color Notes 1.4 and treat them as exposed to availability risk until mitigated.
- Check for and deploy any vendor-issued update, replacement, or supported remediation for Color Notes 1.4.
- If immediate patching is not available, limit use of the application to trusted users and restrict untrusted pasted content where possible.
- Monitor affected hosts for application hangs, crashes, or repeated stop-responding events associated with note creation or paste activity.
- Track the official CVE/NVD record and the disclosed references for any updated remediation guidance.
Evidence notes
This debrief is based only on the supplied corpus: the NVD CVE record, the CVSS v4 metadata, the CWE mapping, and the provided disclosure references. The corpus cites https://www.exploit-db.com/exploits/49952 and https://www.vulncheck.com/advisories/color-notes-denial-of-service-via-long-character-string as disclosure sources, and the official CVE/NVD record links are included below. The supplied record shows a published/modified timestamp of 2026-05-16T16:16:22.170Z.
Official resources
The supplied corpus points to public disclosure material through NVD references to Exploit-DB and a VulnCheck advisory. The CVE record is shown as published and modified on 2026-05-16T16:16:22.170Z in the provided timeline.