CVE-2026-23020: Linux kernel · net: 3com: 3c59x: fix possible null dereference in vortex_probe1()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.15.0-1103.110~20.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1103.110~20.04.1, 5.15.0-1110.119~20.04.1, 5.15.0-1103.112~20.04.1 +57
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 31 Jan 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
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1020.22?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1018.18?arch=source&distro=questingOther 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 patch is available and users should update their linux-azure kernel to the fixed versions listed by Ubuntu (e.g., versions >=5.15.0-1103.110~20.04.1 and others as specified). After updating, a system reboot is required to apply the changes. Due to an ABI change, all third-party kernel modules must be recompiled and reinstalled. Standard system upgrades will handle this automatically if standard kernel metapackages are installed. Follow vendor instructions in the Ubuntu security notices USN-8096-1 and USN-8096-2 for detailed update guidance.
Description
A medium severity vulnerability (CVE-2026-23020) in the Linux kernel's 3com 3c59x network driver was fixed to address a possible null pointer dereference in the vortex_probe1() function. This flaw could cause a denial of service due to a null pointer dereference. The issue affects multiple versions of the linux-azure kernel prior to specific patched versions. The vulnerability is part of a broader set of Linux kernel security fixes released by Ubuntu in March 2026. A patch is available and users are advised to update and reboot their systems. Due to an ABI change, recompilation of third-party kernel modules may be necessary after updating.
References
- ubuntu.com/security/CVE-2026-23020 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23020 (opens in a new tab)
- git.kernel.org/linus/a4e305ed60f7c41bbf9aabc16dd75267194e0de3 (opens in a new tab)
- git.kernel.org/stable/c/053ac9e37eee435e999277c0f1ef890dad6064bf (opens in a new tab)
- git.kernel.org/stable/c/28b2a805609699be7b90020ae7dccfb234be1ceb (opens in a new tab)
- git.kernel.org/stable/c/2f05f7737e16d9a40038cc1c38a96a3f7964898b (opens in a new tab)
- git.kernel.org/stable/c/606872c8e8bf96066730f6a2317502c5633c37f1 (opens in a new tab)
- git.kernel.org/stable/c/6cff14b831dbdb32675b4c7904dcc3eeeaf47e9d (opens in a new tab)
- git.kernel.org/stable/c/a4e305ed60f7c41bbf9aabc16dd75267194e0de3 (opens in a new tab)
- git.kernel.org/stable/c/d82796a57cc0dac1dbef19d913c8f02a8cc7b1a7 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8116-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8141-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8163-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8163-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8243-1 (opens in a new tab)