ToaruOS 1.99.2 is affected by incorrect access control via the kernel.

published 2022-06-08 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-23305

cvss: 8.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 28%
public exploits: 0; none known

ToaruOS 1.99.2 is affected by incorrect access control via the kernel. Improper MMU management and having a low GDT address allows it to be mapped in userland. A call gate can then be written to escalate to CPL 0.

Exploit prediction

0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/mehsauce/kowasuos/blob/master/exploits/kowasu-sysfunc-strikes-back.c referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	8.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
NVD	2.0	7.2	AV:L/AC:L/Au:N/C:C/I:C/A:C

Classification

Weakness

CWE-668 Exposure of Resource to Wrong Sphere

References

github.com /mehsauce/kowasuos/blob/master/exploits/kowasu-sysfunc-strikes-back.c
exploit, third-party-advisory

Sources

CVE List CVE-2021-36710
NVD CVE-2021-36710

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary