critical CVSS 9.8 EPSS 0.42%

CVE-2026-100075·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: RDMA/srpt: Fix srpt_alloc_rw_ctxs() unwind counters When srpt_alloc_rw_ctxs() fails partway through a multi-buffer indirect descriptor, the unwind path destroys RDMA contexts but leaves stale n_rw_ctx and n_rdma values (and a dangling rw_ctxs pointer). Later sq_wr_avail accounting in srpt_queue_response() or srpt_write_pending() can then subtract the wrong number of send queue credits. Reset the counters and clear rw_ctxs after freeing the heap allocation before returning an error.

Severity
critical
Software
Kernel
Fixed in
7.2.6
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at 0.42% — higher than 34% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2026-100075 scores 9.8 on CVSS, so a successful attack would be serious — but at 0.42%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

From: 6.19

Until: 7.2.6

Fixed in: 7.2.6

How to fix this CVE

Update your Linux kernel to version 7.2.6 or later to resolve a critical memory accounting bug in the RDMA/srpt subsystem. This vulnerability affects RDMA context allocation and can lead to incorrect send queue credit calculations, potentially causing denial of service or data integrity issues. Reboot your system after applying the kernel update to ensure the fix is active.

sudo dnf update kernel kernel-devel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Run 'uname -r' to check your current kernel version and compare against the vulnerable range (6.19 to 7.2.5)
  2. Check if RDMA/InfiniBand services are running: 'systemctl status rdma' or 'lsmod | grep rdma'
  3. Search kernel logs for RDMA allocation failures: 'sudo dmesg | grep -i "srpt\|rdma.*fail"'
  4. Verify the fix by confirming kernel version is 7.2.6 or later after reboot: 'uname -r' should show version >= 7.2.6

FAQ

What is CVE-2026-100075?

This vulnerability is a memory accounting bug in the Linux kernel's RDMA/srpt (SRP Target) driver where failed RDMA context allocations leave stale counter values, causing incorrect send queue credit tracking that can trigger denial of service conditions.

Is CVE-2026-100075 being actively exploited?

No, this vulnerability is not currently being actively exploited according to CISA KEV data, and no public exploit code is available.

What versions of Kernel are affected by CVE-2026-100075?

Linux kernel versions 6.19 through 7.2.5 are vulnerable. Version 7.2.6 and later contain the fix.

How do I check if my server is vulnerable to CVE-2026-100075?

Run 'uname -r' to display your kernel version. If it falls between 6.19 and 7.2.5 inclusive, your system is vulnerable. Confirm RDMA is in use with 'lsmod | grep rdma'.

Does Defensia detect CVE-2026-100075?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2026-100075 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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CVE-2026-53384CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails dw8250_probe() registers the 8250 port via serial8250_register_8250_port() and then, if the device has a clock, registers a clock notifier. If clk_notifier_register() fails, probe returns the error but leaves the 8250 port registered. The matching serial8250_unregister_port() lives in dw8250_remove(), which is not called when probe fails, so the port slot stays occupied until the device is rebound or the system is rebooted. The devm-allocated driver data is freed while the port still references it (via the saved private_data and serial_in/serial_out callbacks), so any access to that port slot before a rebind is a use-after-free hazard. Unregister the port on the clk_notifier_register() error path.
CVE-2026-52931CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: batman-adv: tp_meter: avoid use of uninit sender vars batadv_tp_recv_ack() and batadv_tp_stop() are only valid for tp_vars in the BATADV_TP_SENDER role. When called with a BATADV_TP_RECEIVER role, it proceeds to read sender-only members that were never initialized, leading to undefined behavior. This can be triggered when a node that is currently acting as a receiver in an ongoing tp_meter session receives a malicious ACK packet. Guard against this by checking tp_vars->role immediately after the lookup and bailing out if it is not BATADV_TP_SENDER, before any of those members are accessed.
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References

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