Answer in brief
CVE-2026-64027 records a Unknown severity vulnerability in net: shaper: rework the VALID marking (again). 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.
A CVSS score is not reported in the current record. 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.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=93954b40f6a4fc43226c01a15b02732f884500f1 <2417df5e7bb4184b9d3a2988036bf2c46e594545 || >=93954b40f6a4fc43226c01a15b02732f884500f1 <96ea960dd40fd55302e0fd755176f26a95e6a50c || >=93954b40f6a4fc43226c01a15b02732f884500f1 <b8d7519352ba8c6df83259295d4a3bad093cae90 | 2417df5e7bb4184b9d3a2988036bf2c46e594545, 96ea960dd40fd55302e0fd755176f26a95e6a50c, b8d7519352ba8c6df83259295d4a3bad093cae90 |
| Linux/Linuxgeneric | 6.13 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 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: net: shaper: rework the VALID marking (again) Recent commit changed the semantics from NOT_VALID to VALID. I didn't realize that the flags are not stored atomically with the entry in XArray. There's still a race of reader observing a VALID mark for a slot, getting interrupted, writer replacing the entry with a different one, reader continuing, fetching the entry which is now a different pointer than the pointer for which VALID was meant. The biggest consequence of this is that we may see a UAF since net_shaper_rollback() assumed that entries without VALID can be freed without observing RCU. Looks like the XArray marks are buying us nothing at this point. Let's convert the code to an explicit valid field. The smp_load_acquire() / smp_store_release() barriers are marginally cleaner.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-64027 records a Unknown severity vulnerability in net: shaper: rework the VALID marking (again). 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.
A CVSS score is not reported in the current record. 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.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=93954b40f6a4fc43226c01a15b02732f884500f1 <2417df5e7bb4184b9d3a2988036bf2c46e594545 || >=93954b40f6a4fc43226c01a15b02732f884500f1 <96ea960dd40fd55302e0fd755176f26a95e6a50c || >=93954b40f6a4fc43226c01a15b02732f884500f1 <b8d7519352ba8c6df83259295d4a3bad093cae90 | 2417df5e7bb4184b9d3a2988036bf2c46e594545, 96ea960dd40fd55302e0fd755176f26a95e6a50c, b8d7519352ba8c6df83259295d4a3bad093cae90 |
| Linux/Linuxgeneric | 6.13 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 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: net: shaper: rework the VALID marking (again) Recent commit changed the semantics from NOT_VALID to VALID. I didn't realize that the flags are not stored atomically with the entry in XArray. There's still a race of reader observing a VALID mark for a slot, getting interrupted, writer replacing the entry with a different one, reader continuing, fetching the entry which is now a different pointer than the pointer for which VALID was meant. The biggest consequence of this is that we may see a UAF since net_shaper_rollback() assumed that entries without VALID can be freed without observing RCU. Looks like the XArray marks are buying us nothing at this point. Let's convert the code to an explicit valid field. The smp_load_acquire() / smp_store_release() barriers are marginally cleaner.
Quoted source text, attributed separately from HOL analysis.