VulnerabilityPublished 16 Sep 2026Updated 5 Oct 2026

CVE-2026-89780: Linux kernel · net: qualcomm: rmnet: restore skb->dev on deaggregated frames

Affects Linux kernelSource GCVE Database

Not known to be exploited.

Data as of 26 Oct 2026, 12:55 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation evidence

Disclosed: evidence found.
CVE published 16 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Ubuntu 26.04 LTSlinux`pkg:deb/ubuntu/linux?arch=source&distro=resolute`Other threats	Affected 6.17.0-5.5 – 7.0.0-38.38 23 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-aws`pkg:deb/ubuntu/linux-aws?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure`pkg:deb/ubuntu/linux-azure?arch=source&distro=resolute`Other threats	Affected 6.17.0-1003.3 – 7.0.0-1017.17 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure-fde`pkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resolute`Other threats	Affected 7.0.0-1003.3 – 7.0.0-1016.16 9 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gcp`pkg:deb/ubuntu/linux-gcp?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 13 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gke`pkg:deb/ubuntu/linux-gke?arch=source&distro=resolute`Other threats	Affected 7.0.0-1002.3 – 7.0.0-1008.9 6 affected builds	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A fix has been implemented that restores the assignment of skb->dev on deaggregated frames to prevent the null pointer dereference. Users should apply the official kernel updates that include this fix. Since this is a kernel-level issue, upgrading to patched kernel versions is the recommended remediation.

Description

A vulnerability in the Linux kernel's Qualcomm rmnet driver was resolved that could cause a kernel panic due to a null pointer dereference. The issue arises because sub-frames allocated by rmnet_map_deaggregate() have a NULL skb->dev field, and certain command frames trigger a function that attempts to lock a NULL device, leading to a crash. An unprivileged user can exploit this by creating a specific network namespace and sending crafted aggregated frames. This vulnerability affects multiple specific Linux kernel versions used in Ubuntu HWE edge releases.

Impact

Exploitation of this vulnerability results in a kernel panic caused by a null pointer dereference, leading to a denial of service condition. An unprivileged user can trigger this by crafting specific network frames, potentially disrupting system availability.

Summary

The vulnerability in the Linux kernel Qualcomm rmnet driver involves improper handling of skb->dev on deaggregated frames. The function rmnet_map_deaggregate() allocates sub-frames with alloc_skb() but leaves skb->dev as NULL. While skb->dev is normally assigned on the data path, a MAP command frame is dispatched earlier, causing rmnet_map_send_ack() to call netif_tx_lock() on a NULL device pointer. This leads to a kernel panic due to a null pointer dereference in the spinlock code. An unprivileged user can trigger this by unsharing user and network namespaces, creating an rmnet link over a tap device with specific flags, and writing an aggregated frame carrying a flow-control command. The fix restores the assignment of skb->dev to ensure every skb leaving rmnet_map_deaggregate() has a valid device.

GCVE source: db.gcve.eu
OSV ID: UBUNTU-CVE-2026-89780
Osv Schema Version: 1.7.0
Ecosystems: Ubuntu:16.04:LTS, Ubuntu:18.04:LTS, Ubuntu:Pro:18.04:LTS, Ubuntu:Pro:20.04:LTS, Ubuntu:20.04:LTS, Ubuntu:Pro:FIPS-updates:20.04:LTS, Ubuntu:Pro:FIPS:20.04:LTS, Ubuntu:22.04:LTS, Ubuntu:Nvidia-BlueField:22.04:LTS, Ubuntu:Pro:FIPS-preview:22.04:LTS, Ubuntu:Pro:FIPS-updates:22.04:LTS, Ubuntu:Pro:Realtime:22.04:LTS, Ubuntu:24.04:LTS, Ubuntu:Nvidia-BlueField:24.04:LTS, Ubuntu:Pro:FIPS-updates:24.04:LTS, Ubuntu:Pro:Realtime:24.04:LTS, Ubuntu:26.04:LTS

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 24 Oct 2026, 19:13 UTC

Technical details

References

Community reviews

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