Answer in brief
CVE-2025-21955 records a High severity (CVSS 8.8) vulnerability in ksmbd: prevent connection release during oplock break notification. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), 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 8.8. 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), 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:6.14:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=0626e6641f6b467447c81dd7678a69c66f7746cf <09aeab68033161cb54f194da93e51a11aee6144b || >=0626e6641f6b467447c81dd7678a69c66f7746cf <a4261bbc33fbf99b99c80aa3a2c5097611802980 || >=0626e6641f6b467447c81dd7678a69c66f7746cf <f17d1c63a76b0fe8e9c78023a86507a3a6d62cfa || >=0626e6641f6b467447c81dd7678a69c66f7746cf <3aa660c059240e0c795217182cf7df32909dd917 | 09aeab68033161cb54f194da93e51a11aee6144b, a4261bbc33fbf99b99c80aa3a2c5097611802980, f17d1c63a76b0fe8e9c78023a86507a3a6d62cfa, 3aa660c059240e0c795217182cf7df32909dd917 |
| Linux/Linuxgeneric | 5.15 | Not reported |
| Linux/Linuxgeneric | >=0626e6641f6b467447c81dd7678a69c66f7746cf <8e6508c7ecb1802909f294827eff38f301d0c937 || >=0626e6641f6b467447c81dd7678a69c66f7746cf <09aeab68033161cb54f194da93e51a11aee6144b || >=0626e6641f6b467447c81dd7678a69c66f7746cf <a4261bbc33fbf99b99c80aa3a2c5097611802980 || >=0626e6641f6b467447c81dd7678a69c66f7746cf <f17d1c63a76b0fe8e9c78023a86507a3a6d62cfa || >=0626e6641f6b467447c81dd7678a69c66f7746cf <3aa660c059240e0c795217182cf7df32909dd917 | 8e6508c7ecb1802909f294827eff38f301d0c937, 09aeab68033161cb54f194da93e51a11aee6144b, a4261bbc33fbf99b99c80aa3a2c5097611802980, f17d1c63a76b0fe8e9c78023a86507a3a6d62cfa, 3aa660c059240e0c795217182cf7df32909dd917 |
Published upstream
Apr 1, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 30, 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: ksmbd: prevent connection release during oplock break notification ksmbd_work could be freed when after connection release. Increment r_count of ksmbd_conn to indicate that requests are not finished yet and to not release the connection.
Quoted source text, attributed separately from HOL analysis.