Answer in brief
CVE-2026-23436 records a Unknown severity vulnerability in net: shaper: protect from late creation of hierarchy. 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 <719f6784f918f9e32f3ff3b197f900e852223f9d || >=93954b40f6a4fc43226c01a15b02732f884500f1 <d22921727023e7852704965e935f4d1fc83a5ec9 || >=93954b40f6a4fc43226c01a15b02732f884500f1 <d75ec7e8ba1979a1eb0b9211d94d749cdce849c8 | 719f6784f918f9e32f3ff3b197f900e852223f9d, d22921727023e7852704965e935f4d1fc83a5ec9, d75ec7e8ba1979a1eb0b9211d94d749cdce849c8 |
| Linux/Linuxgeneric | 6.13 | Not reported |
Published upstream
Apr 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 5, 2026
In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect from late creation of hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. The netdev may get unregistered in between the time we take the ref and the time we lock it. We may allocate the hierarchy after flush has already run, which would lead to a leak. Take the instance lock in pre- already, this saves us from the race and removes the need for dedicated lock/unlock callbacks completely. After all, if there's any chance of write happening concurrently with the flush - we're back to leaking the hierarchy. We may take the lock for devices which don't support shapers but we're only dealing with SET operations here, not taking the lock would be optimizing for an error case.
Quoted source text, attributed separately from HOL analysis.