CVE-2026-89440: Linux kernel · mmc: via-sdmmc: stop card-detect handling on probe failure
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 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.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| 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 in the Linux kernel source to properly disable and free the interrupt and cancel scheduled work on probe failure. Users should apply the official kernel update that includes this patch. No other mitigation steps are indicated.
Description
In the Linux kernel, the following vulnerability has been resolved: mmc: via-sdmmc: stop card-detect handling on probe failure request_irq() registers the SD card-detect interrupt and the probe enables it before mmc_add_host() runs. If mmc_add_host() fails, the error path only unmaps the registers and returns: the interrupt stays registered, so the handler keeps running against the host once it is freed. via_sdc_isr() dereferences sdhost and its MMIO base and schedules carddet_work, which via_sdc_card_detect() also runs against freed memory through its container_of() dereference. Add a probe-error path that disables and frees the interrupt and cancels carddet_work before unmapping. carddet_work can re-enable the device interrupt via via_reset_pcictrl(), which restores PCIINTCTRL, so mask it again after cancelling the work. This issue was found by an in-house static analysis tool and confirmed by manual code review.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89440 (opens in a new tab)
- git.kernel.org/stable/c/088eaa92fcebaa6b957ccf9635afdf39643a577d (opens in a new tab)
- git.kernel.org/stable/c/2550f89589caad7402d618d7dffc038582c94b6b (opens in a new tab)
- git.kernel.org/stable/c/c2b8a624911999399cc14822fec3e35032b3cee4 (opens in a new tab)
- git.kernel.org/stable/c/efe7f25dd27e35063477b4b0e7eed3675669fd99 (opens in a new tab)
- ubuntu.com/security/CVE-2026-89440 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89440 (opens in a new tab)
- git.kernel.org/linus/088eaa92fcebaa6b957ccf9635afdf39643a577d (opens in a new tab)