Answer in brief
CVE-2026-74739 records a High severity (CVSS 7.8) vulnerability in net/sched: cls_u32: skip hash tables in u32_bind_class(). 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.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=07d79fc7d94e3f884b8b1c95aa615b202bb5e4c1 <ec5f3005586a785689fd568361b0c5925cb1548b || >=07d79fc7d94e3f884b8b1c95aa615b202bb5e4c1 <19d114b93c94bdef70496f26685c2a6b242f41b3 || >=07d79fc7d94e3f884b8b1c95aa615b202bb5e4c1 <594a064d603202b9ee21e07679d854e5c1750cc4 || >=07d79fc7d94e3f884b8b1c95aa615b202bb5e4c1 <31f26a95eeee926946809ac456c61a3217936a62 || >=07d79fc7d94e3f884b8b1c95aa615b202bb5e4c1 <e71f8e9ed6f311410b14741f6012afe01869c0fa || >=07d79fc7d94e3f884b8b1c95aa615b202bb5e4c1 <6d3724e616faf952c3adcf8414fc21a828ef3709 | ec5f3005586a785689fd568361b0c5925cb1548b, 19d114b93c94bdef70496f26685c2a6b242f41b3, 594a064d603202b9ee21e07679d854e5c1750cc4, 31f26a95eeee926946809ac456c61a3217936a62, e71f8e9ed6f311410b14741f6012afe01869c0fa, 6d3724e616faf952c3adcf8414fc21a828ef3709 |
| Linux/Linuxgeneric | 4.14 | Not reported |
Published upstream
Aug 26, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 26, 2026
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_u32: skip hash tables in u32_bind_class() u32_walk() enumerates both struct tc_u_hnode and struct tc_u_knode through the walker callback. u32_bind_class() unconditionally casts the passed fh to tc_u_knode and accesses &n->res, so when fh is actually a tc_u_hnode, which has no tcf_result member, this results in a slab-out-of-bounds read of res->classid in tc_cls_bind_class(). The issue can be reproduced with the following commands: tc qdisc add dev lo root handle 1: hfsc tc class add dev lo parent 1: classid 1:1 hfsc sc rate 1000kbit tc filter add dev lo parent 1:1 protocol ip prio 1 u32 match u32 0 0 flowid 1:1 tc class add dev lo parent 1: classid 1:2 hfsc sc rate 2000kbit Fix this by skipping hash tables via the TC_U32_KEY(handle) check.
Quoted source text, attributed separately from HOL analysis.