CVE-2021-3629
A flaw was found in Undertow. A potential security issue in flow control handling by the browser over http/2 may potentially cause…
- Published
- Updated
- Reserved
- Assigned by
- redhat
Description
A flaw was found in Undertow. A potential security issue in flow control handling by the browser over http/2 may potentially cause overhead or a denial of service in the server. The highest threat from this vulnerability is availability. This flaw affects Undertow versions prior to 2.0.40.Final and prior to 2.2.11.Final.
Timeline
ID reserved
By redhat
- 11 months later
· 11 months later
Published
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 1.3% · top 29% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.
Weakness
Affected products
undertow
- affected undertow 2.0.40.Final, undertow 2.2.11.Final
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Mavenio.undertow:undertow-coreGHSA-rf6q-vx79-mjxr (opens in a new tab)
References (2)
- https://bugzilla.redhat.com/show_bug.cgi?id=1977362 (opens in a new tab)x_refsource_MISCx_transferred
- https://security.netapp.com/advisory/ntap-20220729-0008/ (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-rf6q-vx79-mjxr (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-3629)Record last updated .