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CVE-2021-3635
A flaw was found in the Linux kernel netfilter implementation in versions prior to 5.5-rc7. A user with root (CAP_SYS_ADMIN) access is…
Medium4.4EPSS 0.25%
- Published
- Updated
- Reserved
- Assigned by
- redhat
Description
A flaw was found in the Linux kernel netfilter implementation in versions prior to 5.5-rc7. A user with root (CAP_SYS_ADMIN) access is able to panic the system when issuing netfilter netflow commands.
Timeline
ID reserved
By redhat
- 42 days later
· 42 days later
Published
- 3 years later
· 3 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 | Medium4.4 | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.25% · top 84% of all CVEs (7 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.4.
Weakness
Affected products
kernel
- affected kernel 5.5-rc7
References (1)
- https://bugzilla.redhat.com/show_bug.cgi?id=1976946 (opens in a new tab)x_refsource_MISCx_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 Advisories (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-2021-3635)Record last updated .