CVE-2025-48990: nekernel · Heap-based Buffer Overflow
Affects nekernelSource CVE Database V5
Not known to be exploited · CVSS 8.6 High.
Data as of 26 Oct 2026, 09:15 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 2 Jun 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
GitHubnekernel-org/nekernelpkg:github/nekernel-org/nekernelOther 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
European organizations using NeKernal 0.0.2 should immediately upgrade to a patched version once available, or apply the minimal patch that removes the overflow-causing line in rt_copy_memory. Since the patch does not add bounds checking, organizations should also conduct thorough code audits and implement additional memory safety checks around this function if possible. Employing runtime protections such as heap canaries, address space layout randomization (ASLR), and control-flow integrity (CFI) can help mitigate exploitation attempts. Restricting local access to trusted users and systems reduces the attack surface. For embedded or specialized deployments, consider isolating NeKernal-based systems within segmented network zones and monitoring for anomalous behavior indicative of exploitation attempts. Additionally, organizations should maintain up-to-date inventories of systems running NeKernal and conduct vulnerability scanning to identify affected versions. Incident response plans should include procedures for detecting and responding to heap overflow exploitation attempts.
Description
NeKernal is a free and open-source operating system stack. Version 0.0.2 has a 1-byte heap overflow in `rt_copy_memory`, which unconditionally wrote a null terminator at `dst[len]`. When `len` equals the size of the destination buffer (256 bytes), that extra `'\0'` write overruns the buffer by one byte. To avoid breaking existing callers or changing the public API, the patch in commit fb7b7f658327f659c6a6da1af151cb389c2ca4ee takes a minimal approach: it simply removes the overflow-causing line without adding bounds checks or altering the function signature.