CVE-2025-40126: Linux kernel · sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 5.15.0-1100.107~20.04.2 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 13:47 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 13% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1100.107~20.04.2, 5.15.0-1110.119~20.04.1, 5.15.0-1100.109~20.04.1 +67
Exploitation evidence
Disclosed: evidence found.
CVE published 12 Nov 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.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linuxpkg:deb/ubuntu/linux@6.17.0-14.14?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1007.7?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1008.8?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@6.17.0-1007.7?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1007.7?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.
Description
In the Linux kernel, the following vulnerability has been resolved: sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC The referenced commit introduced exception handlers on user-space memory references in copy_from_user and copy_to_user. These handlers return from the respective function and calculate the remaining bytes left to copy using the current register contents. This commit fixes a couple of bad calculations. This will fix the return value of copy_from_user and copy_to_user in the faulting case. The behaviour of memcpy stays unchanged.
References
- ubuntu.com/security/CVE-2025-40126 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-40126 (opens in a new tab)
- git.kernel.org/linus/4fba1713001195e59cfc001ff1f2837dab877efb (opens in a new tab)
- git.kernel.org/stable/c/0bf3dc3a2156f1c5ddaba4b85d09767874634114 (opens in a new tab)
- git.kernel.org/stable/c/41c18baee66134e6ef786eb075c1b6adb22432b0 (opens in a new tab)
- git.kernel.org/stable/c/4fba1713001195e59cfc001ff1f2837dab877efb (opens in a new tab)
- git.kernel.org/stable/c/57c278500fce3cd4e1c540700c0b05426a958393 (opens in a new tab)
- git.kernel.org/stable/c/59424dc0d0e044b2eb007686a4724ddd91d57db5 (opens in a new tab)
- git.kernel.org/stable/c/674ff598148a28bae0b5372339de56f2abf0b1d1 (opens in a new tab)
- git.kernel.org/stable/c/7de3a75bbc8465d816336c74d50109e73501efab (opens in a new tab)
- git.kernel.org/stable/c/9b137f277cc3297044aabd950f589e505d30104c (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8030-1 (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-8029-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8033-5 (opens in a new tab)