CVE-2025-39998: Linux kernel · scsi: target: target_core_configfs: Add length check to avoid buffer overflow
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High · fixed in 5.15.0-1100.107~20.04.2 : patch Linux kernel soon.
Data as of 28 Oct 2026, 11:19 UTC
- Patch
- Available – fixed in 5.15.0-1100.107~20.04.2, 5.15.0-1110.119~20.04.1, 5.15.0-1114.123~20.04.1 +69
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 15 Oct 2025
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.
Patches and advisories
- ubuntu.com/security/notices/USN-8033-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8034-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8034-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-6 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-7 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-8 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8100-1 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linuxpkg:deb/ubuntu/linux?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle?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 has been released in Linux kernel versions 5.15.0-1100.107~20.04.2 and later. Users should apply the official kernel updates provided by their Linux distribution vendors, such as the Ubuntu security notice USN-8033-1. After updating, a system reboot is required to apply the fixes. No additional mitigation steps are necessary beyond applying the official patches.
Description
CVE-2025-39998 is a buffer overflow vulnerability in the Linux kernel's SCSI target subsystem, specifically in the target_core_configfs component. The flaw arises from improper length checking when formatting strings into a fixed-size buffer, potentially causing a buffer overflow error. This vulnerability has been fixed in Linux kernel versions 5.15.0-1100.107~20.04.2 and later. The issue has a high severity score and could lead to denial of service or system instability if exploited.
References
- ubuntu.com/security/CVE-2025-39998 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-39998 (opens in a new tab)
- git.kernel.org/linus/27e06650a5eafe832a90fd2604f0c5e920857fae (opens in a new tab)
- git.kernel.org/stable/c/27e06650a5eafe832a90fd2604f0c5e920857fae (opens in a new tab)
- git.kernel.org/stable/c/4b292286949588bd2818e66ff102db278de8dd26 (opens in a new tab)
- git.kernel.org/stable/c/53c6351597e6a17ec6619f6f060d54128cb9a187 (opens in a new tab)
- git.kernel.org/stable/c/a150275831b765b0f1de8b8ff52ec5c6933ac15d (opens in a new tab)
- git.kernel.org/stable/c/e73fe0eefac3e15bf88fb5b4afae4c76215ee4d4 (opens in a new tab)
- git.kernel.org/stable/c/f03aa5e39da7d045615b3951d2a6ca1d7132f881 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8034-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8034-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-6 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-7 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-8 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-1 (opens in a new tab)