Answer in brief
CVE-2026-98234 records a Unknown severity vulnerability in net/sched: hhf: cap hh_flows_limit at change time. 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 | >=10239edf86f137ce4c39b62ea9575e8053c549a0 <7adfd0a42174b85c6bd678858ecd6674f403f336 || >=10239edf86f137ce4c39b62ea9575e8053c549a0 <35fd423a5c5132c6f4321f6c4f0a7b4b90af830c || >=10239edf86f137ce4c39b62ea9575e8053c549a0 <06d2a101e89063cb0b9b459104db48bdfb0a797d || >=10239edf86f137ce4c39b62ea9575e8053c549a0 <d8e2f1f0263b7c97b222c06070cccf13e0ab7112 || >=10239edf86f137ce4c39b62ea9575e8053c549a0 <f3f4a5cb4a6e9b1f1f25d34dfc25f836a1601db4 || >=10239edf86f137ce4c39b62ea9575e8053c549a0 <1731ff1d20489afe4cd01b7d16d37f324746ac54 || >=10239edf86f137ce4c39b62ea9575e8053c549a0 <f6547d27ce2093c5627636fb63dd0b7523c466f9 || >=10239edf86f137ce4c39b62ea9575e8053c549a0 <2cef2588c995722a901368def30befeef9ae55c6 | 7adfd0a42174b85c6bd678858ecd6674f403f336, 35fd423a5c5132c6f4321f6c4f0a7b4b90af830c, 06d2a101e89063cb0b9b459104db48bdfb0a797d, d8e2f1f0263b7c97b222c06070cccf13e0ab7112, f3f4a5cb4a6e9b1f1f25d34dfc25f836a1601db4, 1731ff1d20489afe4cd01b7d16d37f324746ac54, f6547d27ce2093c5627636fb63dd0b7523c466f9, 2cef2588c995722a901368def30befeef9ae55c6 |
| Linux/Linuxgeneric | 3.14 | Not reported |
Published upstream
Oct 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 6, 2026
In the Linux kernel, the following vulnerability has been resolved: net/sched: hhf: cap hh_flows_limit at change time hhf_change() stores TCA_HHF_HH_FLOWS_LIMIT with no upper bound. A huge hh_flows_limit lets each new heavy-hitter flow pass the hh_flows_current_cnt check in alloc_new_hh() and forces a fixed-size kzalloc(GFP_ATOMIC) per flow under spoofed traffic, for unbounded memory growth. Bound the attribute with NLA_POLICY_MAX() at 2*HH_FLOWS_CNT (the hhf_init() default) and report the rejected value via extack. The deprecated nested parse is kept: legacy tc does not set NLA_F_NESTED on TCA_OPTIONS. Configs relying on hh_limit above the default were relying on unbounded, unsafe behaviour and are not supported going forward. hhf_init() also ran hhf_change() before setting the default hh_flows_limit, so a user-supplied hh_limit at add time was clobbered back to 2048. Set the default before hhf_change() so the configured value sticks. This is a follow-up to commit eb56a495f59b ("net/sched: hhf: clamp quantum in change and init paths"), which bounded the quantum of the same qdisc; the hh_flows_limit bound is the remaining unbounded knob of that series' scope. Conditions to recreate the bug: CAP_NET_ADMIN in a user namespace; tc qdisc change dev X root hhf hh_limit 4294967295 succeeds and the value is echoed by tc qdisc show, unbounding heavy-hitter flow allocations; also tc qdisc add dev X root hhf hh_limit 500 stores 2048 instead of 500.
Quoted source text, attributed separately from HOL analysis.