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CVE-2026-43383net/tcp-md5: Fix MAC comparison to be constant-time
- 9.4CriticalCVSS base score
- 0.54%Exploitation in 30 daysEPSS · top 54% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: net/tcp-md5: Fix MAC comparison to be constant-time To prevent timing attacks, MACs need to be compared in constant time. Use the appropriate helper function for this.
Timeline
ID reserved
By Linux
- 7 days later
· 7 days later
Published
- 5 months later
· 5 months 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 |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | Critical9.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H |
| NVDNVD · Modified | 3.1 | Critical9.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.54% · top 54% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.4.
Affected products
- affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc – < 821c8751fdeecdeecabeb11704dd33439c9e4bbc
- affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc – < ff44ec94d4fc8348600a69de0a8fa1102c23bce8
- affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc – < 345a9530756528d7ca407663d659c3c40e75c3dd
- affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc – < 5d305a95130a8d08b9545e47f1e18d29d59866cb
- affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc – < 02669e2a4d207068edce7e8b5fafd85822018ce6
- affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc – < ae3831b44f477de048287493e184fc3ff913b624
- affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc – < b502e97e29d791ff7a8051f29a414535739be218
- affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc – < 46d0d6f50dab706637f4c18a470aac20a21900d3
- affected 2.6.20
- unaffected < 2.6.20
- unaffected 5.10.253 – ≤ 5.10.*
- unaffected 5.15.210 – ≤ 5.15.*
- unaffected 6.1.167 – ≤ 6.1.*
- unaffected 6.6.130 – ≤ 6.6.*
- unaffected 6.12.78 – ≤ 6.12.*
- unaffected 6.18.19 – ≤ 6.18.*
- unaffected 6.19.9 – ≤ 6.19.*
- unaffected 7.0 – ≤ *
References
References8
- https://git.kernel.org/stable/c/821c8751fdeecdeecabeb11704dd33439c9e4bbc (opens in a new tab)
- https://git.kernel.org/stable/c/ff44ec94d4fc8348600a69de0a8fa1102c23bce8 (opens in a new tab)
- https://git.kernel.org/stable/c/345a9530756528d7ca407663d659c3c40e75c3dd (opens in a new tab)
- https://git.kernel.org/stable/c/5d305a95130a8d08b9545e47f1e18d29d59866cb (opens in a new tab)
- https://git.kernel.org/stable/c/02669e2a4d207068edce7e8b5fafd85822018ce6 (opens in a new tab)
- https://git.kernel.org/stable/c/ae3831b44f477de048287493e184fc3ff913b624 (opens in a new tab)
- https://git.kernel.org/stable/c/b502e97e29d791ff7a8051f29a414535739be218 (opens in a new tab)
- https://git.kernel.org/stable/c/46d0d6f50dab706637f4c18a470aac20a21900d3 (opens in a new tab)
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-2026-28689 (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://cveledger.app/cve/CVE-2026-43383)Record last updated .