CVE-2021-33623
No exploitation reported by the sources we read.
- Published2021-05-28
- Fixed in4.0.1 · 3.0.1
- WeaknessCWE-400
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
The trim-newlines package before 3.0.1 and 4.x before 4.0.1 for Node.js has an issue related to regular expression denial-of-service (ReDoS) for the .end() method.
Timeline
dates in UTC- 2021-05-2818:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-33623?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-33623?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 4.0 | ≥ 4.0.0, < 4.0.1 | 4.0.1 | NVD |
| 3.0 | < 3.0.1 | 3.0.1 | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 10.0 | = 10.0 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| — | all versions | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Vendor advisories
Red Hat Security Advisory: Cluster Observability Operator 1.5.0
Fix
- Update Trim-newlines project trim-newlines to 4.0.1 · 3.0.1
- Vendor fix Red Hat Product Security RHSA-2026:34342 · 4 productsBefore applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
Advisories and patches
- github.comPatch · Release Notes
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
- NVDCVSS 3.17.5read 2026-10-23
- NVDCVSS 2.05read 2026-10-23
- NVDweakness (CWE)CWE-400read 2026-10-23
- FIRST EPSSEPSS score2.9 %2026-10-22
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- 2021-05-28
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-33623?
Is CVE-2021-33623 actively exploited?
What is the CVSS score for CVE-2021-33623?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.