In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: TC, Check if flow is PEER before acquiring devcom lock
In case __mlx5e_add_fdb_flow() fails in lower levels, the flow is
deleted via mlx5e_tc_del_flow(), and mlx5e_tc_del_flow() is acquiring
ESW devcom lock without condition. In addition, in case of peer_flow,
__mlx5e_add_fdb_flow() is called while holding ESW devcom comp lock.
This results in an AA deadlock.
To fix this, introduce a new PEER flag that is set on flows created as
peer flows (the duplicate flows on peer devices), and check it in
mlx5e_tc_del_flow() before acquiring ESW devcom lock.
Lockdep splat:
============================================
WARNING: possible recursive locking detected
============================================
Possible unsafe locking scenario:
CPU0
----
lock(&comp->lock_key#2);
lock(&comp->lock_key#2);
* DEADLOCK *
Call Trace:
dump_stack_lvl+0x69/0xa0
print_deadlock_bug.cold+0xbd/0xca
__lock_acquire+0x1671/0x2ec0
lock_acquire+0x10e/0x2e0
down_read+0x95/0x430
mlx5_devcom_for_each_peer_begin+0x4e/0xe0 [mlx5_core]
mlx5e_tc_del_flow+0x11d/0xa70 [mlx5_core]
mlx5e_flow_put+0x99/0x100 [mlx5_core]
__mlx5e_add_fdb_flow+0x409/0xf00 [mlx5_core]
mlx5e_configure_flower+0x2a86/0x4100 [mlx5_core]
mlx5e_rep_setup_tc_cls_flower+0x12f/0x1b0 [mlx5_core]
mlx5e_rep_setup_tc_cb+0x153/0x750 [mlx5_core]
tc_setup_cb_add+0x1dc/0x470
fl_change+0x2f4d/0x626d [cls_flower]
tc_new_tfilter+0x79b/0x2310
rtnetlink_rcv_msg+0x778/0xad0
do_syscall_64+0x70/0x960
entry_SYSCALL_64_after_hwframe+0x4b/0x53
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
- EG Severity
- Not assessed: no CVSS publishedA missing CVSS is not a severity of zero.
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- No SSVC decision: EchelonGraph has not assessed this CVECISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the BOD 26-04 block below.
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it