Is CVE-2026-31658 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-31658 being exploited in the wild.

How severe is CVE-2026-31658?

Medium severity, with a CVSS score of 5.5, published 24 April 2026.

Which products and versions are affected?

Linux Kernel versions before 6.9.1; Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP V3.1.5, V3.1.6.

Is there a fix for CVE-2026-31658?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-31658 attacked?

It is attacked with local access, in an operating system.

Am I affected by CVE-2026-31658?

Check whether you run Linux Kernel or Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-31658: Linux Kernel memory leak in Altera TSE Ethernet driver

CVE-2026-31658 · Severity: medium · CVSS 5.5 · Published 2026-04-24

A memory leak vulnerability exists in the Altera Ethernet driver within the Linux kernel. When the system encounters a specific hardware communication error (DMA mapping failure), it fails to release allocated memory. Over time, this can lead to a depletion of system resources, potentially causing the device to slow down or crash, impacting operational availability.

Technologies: Linux Kernel, Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP. Vendors: Linux, Siemens.

Quick answers

Is CVE-2026-31658 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-31658 being exploited in the wild.
How severe is CVE-2026-31658?: Medium severity, with a CVSS score of 5.5, published 24 April 2026.
Which products and versions are affected?: Linux Kernel versions before 6.9.1; Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP V3.1.5, V3.1.6.
Is there a fix for CVE-2026-31658?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-31658 attacked?: It is attacked with local access, in an operating system.
Am I affected by CVE-2026-31658?: Check whether you run Linux Kernel or Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A memory leak (CWE-401) exists in the Altera Triple-Speed Ethernet (TSE) driver (drivers/net/ethernet/altera/altera_tse_main.c) within the Linux kernel. The vulnerability is located in the tse_start_xmit() function, where a failure in dma_map_single() results in the function returning NETDEV_TX_OK without freeing the associated socket buffer (skb). Because the networking stack is notified that the packet was successfully consumed, the memory is never reclaimed. An attacker with local access could potentially trigger this condition to exhaust system memory, leading to a denial-of-service. Patches have been released across multiple stable kernel branches to include the missing dev_kfree_skb_any() call.

Affected products

Linux Linux Kernel versions before 6.9.1
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP V3.1.5, V3.1.6

Timeline

2026-04-01: disclosed: Initial patch submitted by David Carlier
2026-04-24: advisory: NVD publication date

References

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