CVE-2025-40245: Linux kernel · nios2: ensure that memblock.current_limit is set when setting pfn limits On
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 4% 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 4 Dec 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 2026-10-25.
What to do
AI-suggested
A fix has been implemented in the Linux kernel to correctly initialize memblock.current_limit during boot on nios2 with CONFIG_FLATMEM. Users should apply the official kernel patch or update to a fixed kernel version once available.
Description
A vulnerability in the Linux kernel on the nios2 architecture with CONFIG_FLATMEM set could cause kernel-level paging failures and panics due to incorrect memory limit calculations. The issue arises because memblock.current_limit is not properly initialized during boot, potentially allowing max_low_pfn to exceed valid memory ranges. This has been resolved by ensuring memblock.current_limit is correctly set based on available memory limits.
References
- nvd.nist.gov/vuln/detail/CVE-2025-40245 (opens in a new tab)
- git.kernel.org/stable/c/25f09699edd360b534ccae16bc276c3b52c471f3 (opens in a new tab)
- git.kernel.org/stable/c/5c3e38a367822f036227dd52bac82dc4a05157e2 (opens in a new tab)
- git.kernel.org/stable/c/8912814f14e298b83df072fecc1f7ed1b63b1b2c (opens in a new tab)
- git.kernel.org/stable/c/90f5f715550e07cd6a51f80fc3f062d832c8c997 (opens in a new tab)
- git.kernel.org/stable/c/a20b83cf45be2057f3d073506779e52c7fa17f94 (opens in a new tab)
- git.kernel.org/stable/c/b1ec9faef7e36269ca3ec890972a78effbaeb975 (opens in a new tab)