Answer in brief
CVE-2026-63995 records a High severity (CVSS 7.8) vulnerability in ethtool: cmis: validate start_cmd_payload_size from module. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=c4f78134d45c9619339c96b4bea380b1d0699788 <63112b4515469d00008452d9cfe3fb3bf1aa2df3 || >=c4f78134d45c9619339c96b4bea380b1d0699788 <0696709e951be54c699664adf546d16e28974d53 || >=c4f78134d45c9619339c96b4bea380b1d0699788 <a46340da00385be7fb16c62425ebc20006f2d5d8 || >=c4f78134d45c9619339c96b4bea380b1d0699788 <12c2496a71f82f63617971ca9b730dffa05cf58b | 63112b4515469d00008452d9cfe3fb3bf1aa2df3, 0696709e951be54c699664adf546d16e28974d53, a46340da00385be7fb16c62425ebc20006f2d5d8, 12c2496a71f82f63617971ca9b730dffa05cf58b |
| Linux/Linuxgeneric | 6.11 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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.
Quoted source text, attributed separately from HOL analysis.