Tracker / CVE-2025-21703
CVE-2025-21703
High 7.8
In the Linux kernel, the following vulnerability has been resolved: netem: Update sch->q.qlen before qdisc_tree_reduce_backlog() qdisc_tree_reduce_backlog() notifies parent qdisc only if child qdisc becomes empty, therefore we need to reduce the backlog of the child qdisc before calling it. Otherwise it would miss the opportunity to call cops->qlen_notify(), in the case of DRR, it resulted in UAF since DRR uses ->qlen_notify() to maintain its active list.
Affected products and versions
| linux | linux_kernel |
|---|---|
| linux | linux_kernel · 5.10.232 → 5.10.235 |
| linux | linux_kernel · 5.15.175 → 5.15.179 |
| linux | linux_kernel · 5.4.288 → 5.4.291 |
| linux | linux_kernel · 6.1.121 → 6.1.129 |
| linux | linux_kernel · 6.12.6 → 6.12.14 |
| linux | linux_kernel · 6.13 → 6.13.3 |
| linux | linux_kernel · 6.6.67 → 6.6.78 |
Analysis
This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.