CVE-2021-3597A flaw was found in undertow. The HTTP2SourceChannel fails to write the final frame under some circumstances, resulting in a denial of…
- 5.9MediumCVSS base score
- 1.2%Exploitation in 30 daysEPSS · top 32% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
A flaw was found in undertow. The HTTP2SourceChannel fails to write the final frame under some circumstances, resulting in a denial of service. The highest threat from this vulnerability is availability. This flaw affects Undertow versions prior to 2.0.35.SP1, prior to 2.2.6.SP1, prior to 2.2.7.SP1, prior to 2.0.36.SP1, prior to 2.2.9.Final and prior to 2.0.39.Final.
Timeline
ID reserved
By redhat
- 12 months later
· 12 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)
- 1.2% · top 32% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.
Affected products
undertow
- affected undertow 2.0.35.SP1, undertow 2.2.6.SP1, undertow 2.2.7.SP1, undertow 2.0.36.SP1, undertow 2.2.9.Final, undertow 2.0.39.Final
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Mavenio.undertow:undertow-coreGHSA-mfhv-gwf8-4m88 (opens in a new tab)
References
References2
- https://bugzilla.redhat.com/show_bug.cgi?id=1970930 (opens in a new tab)x_refsource_MISCx_transferred
- https://security.netapp.com/advisory/ntap-20220804-0003/ (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)
- EUVD EUVD-2022-4550 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-mfhv-gwf8-4m88 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-3597)Record last updated .