CVE-2026-63995ethtool: cmis: validate start_cmd_payload_size from module
- 7.8HighCVSS base score
- 0.13%Exploitation in 30 daysEPSS · top 97% 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: ethtool: cmis: validate start_cmd_payload_size from module The CMIS firmware update code reads start_cmd_payload_size from the module's FW Management Features CDB reply and uses it directly as the byte count for memcpy. The destination buffer is 112 bytes (ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH - 8). So a malicious module (or corrupted response) can cause a OOB write later on in cmis_fw_update_start_download(). Let's error out. If modules that expect longer LPL writes actually exist we should revisit. struct cmis_cdb_start_fw_download_pl's definition has to move, no change there.
Timeline
ID reserved
By Linux
Published
- 3 months later
· 3 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 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.13% · top 97% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected c4f78134d45c9619339c96b4bea380b1d0699788 – < 63112b4515469d00008452d9cfe3fb3bf1aa2df3
- affected c4f78134d45c9619339c96b4bea380b1d0699788 – < 0696709e951be54c699664adf546d16e28974d53
- affected c4f78134d45c9619339c96b4bea380b1d0699788 – < a46340da00385be7fb16c62425ebc20006f2d5d8
- affected c4f78134d45c9619339c96b4bea380b1d0699788 – < 12c2496a71f82f63617971ca9b730dffa05cf58b
- affected 6.11
- unaffected < 6.11
- unaffected 6.12.93 – ≤ 6.12.*
- unaffected 6.18.35 – ≤ 6.18.*
- unaffected 7.0.12 – ≤ 7.0.*
- unaffected 7.1 – ≤ *
References
References4
- https://git.kernel.org/stable/c/63112b4515469d00008452d9cfe3fb3bf1aa2df3 (opens in a new tab)
- https://git.kernel.org/stable/c/0696709e951be54c699664adf546d16e28974d53 (opens in a new tab)
- https://git.kernel.org/stable/c/a46340da00385be7fb16c62425ebc20006f2d5d8 (opens in a new tab)
- https://git.kernel.org/stable/c/12c2496a71f82f63617971ca9b730dffa05cf58b (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-2026-45568 (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-2026-63995)Record last updated .