CVE-2025-37797: stato di sfruttamento e disponibilità della patch
CVE-2025-37797 · CVSS 7.8 HIGH · EPSS <1%
In the Linux kernel, the following vulnerability has been resolved:
net_sched: hfsc: Fix a UAF vulnerability in class handling
This patch fixes a Use-After-Free vulnerability in the HFSC qdisc class
handling. The issue occurs due to a time-of-check/time-of-use condition
in hfsc_change_class() when working with certain child qdiscs like netem
or codel.
The vulnerability works as follows:
1. hfsc_change_class() checks if a class has packets (q.qlen != 0)
2. It then calls qdisc_peek_len(), which for certain qdiscs (e.g.,
codel, netem) might drop packets and empty the queue
3. The code continues assuming the queue is still non-empty, adding
the class to vttree
4. This breaks HFSC scheduler assumptions that only non-empty classes
are in vttree
5. Later, when the class is destroyed, this can lead to a Use-After-Free
The fix adds a second queue length check after qdisc_peek_len() to verify
the queue wasn't emptied.
CVE-2025-37797 viene sfruttato?
Non è nel catalogo CISA KEV.
EPSS stima la probabilità di sfruttamento nei prossimi 30 giorni al <1%.
Codice di exploit pubblico: nessuno trovato nelle fonti monitorate.
Quali prodotti e versioni sono interessati?
Nessun elenco di pacchetti interessati registrato qui.