CVE-2026-89511 qede: Fix NULL pointer dereference in TPA fragment processing
A NULL pointer dereference in the qede network driver causes a kernel panic during TPA fragment processing under memory pressure.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89511?
CVE-2026-89511 is a high-severity vulnerability in Linux, published on 11 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
qede: Fix NULL pointer dereference in TPA fragment processing
Under memory pressure, the qede driver encounters NULL pointer dereferences when processing TPA continuation fragments.
Commit 8a8633978b84 ("qede: Add build_skb() support.") accidentally dropped the assignment of tpa_info->buffer.data in qede_tpa_start().
When memory pressure causes an SKB allocation failure in qede_tpa_start(), the driver sets tpa_start_fail = true and attempts to recycle the physical page later in qede_tpa_end() via qede_reuse_page(). However, because buffer.data was left uninitialized (NULL), qede_reuse_page() pushes a "ghost" BD (valid DMA mapping but NULL data pointer) back into the active Rx ring.
The next time the hardware uses this ring slot, it passes a NULL page to qede_fill_frag_skb(), causing a kernel panic.
Example crash from production system: BUG: unable to handle kernel NULL pointer dereference at 0x8 RIP: qede_fill_frag_skb+0x96/0x430 [qede] Call Trace: qede_rx_int+0xb06/0x1de0 qede_poll+0x2f4/0x6c0 __napi_poll+0x2d/0x130
Fix the root cause by restoring the tpa_info->buffer.data assignment in qede_tpa_start(), ensuring valid pages are correctly tracked and recycled. Additionally, update the stale comment for struct qede_agg_info::buffer to reflect its current usage.
Which versions are affected by CVE-2026-89511?
How do I fix CVE-2026-89511?
Apply the vendor's patch.
Is CVE-2026-89511 being exploited?
There is no known exploitation of CVE-2026-89511 in the wild and no public exploit code.
Sources
Also known as AZL-100094, BELL-CVE-2026-89511, DEBIAN-CVE-2026-89511, GHSA-7j5j-83jx-4ffc, UBUNTU-CVE-2026-89511.