Out-of-Bounds Write in Linux Openatom (CVE-2021-33656)
Summary
Out-of-bounds write in Linux Openatom (CVE-2021-33656). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A weakness called CVE-2021-33656 was discovered in Linux Openatom.
In plain terms, it is an out-of-bounds write that can let attackers hijack the program.
Severity is Medium (CVSS 6.8/10). Exploitation requires specific conditions but can cause real harm if successful.
What you should do: update the affected software to the latest version. If unsure, ask your IT team or search the vendor's site for "Linux Openatom CVE-2021-33656".
CVE-2021-33656 (Linux Openatom). Severity: Medium / CVSSv3 6.8. Category: CWE-787.
Response plan:
- Check the vendor advisory for affected versions and the patched release.
- If a vulnerable version is running in production, schedule maintenance (urgency from KEV/CVSS).
- If no patch yet, mitigate via WAF rule, disabling the affected feature, etc.
- Monitor logs / SIEM for known IOC and PoC signatures of this CVE.
PoCs and fix commits: see the 'References' section, MITRE, and NVD.
A weakness (CVE-2021-33656) in Linux Openatom. In plain words, it is an out-of-bounds write that can let attackers hijack the program.
Target versions of Linux Openatom (see vendor advisory). If running in production, identify exposure immediately.
Severity: Medium (CVSS 6.8/10). Exploitation requires specific conditions but can cause real harm if successful.
Update to the patched release as listed in the vendor advisory. (Typical mitigation pattern for CWE-787)
If a patch is not yet available, consider disabling the affected feature, applying WAF rules, blocking via network ACLs, or isolating the vulnerable version.
Check version information, scan dependencies via SBOM, and monitor SIEM for IOC and PoC signatures related to this CVE.
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Ubuntu UBUNTU-CVE-2021-33656 linux-aws Fixed in: 4.4.0-1113.119
References
- advisory lists.debian.org
- advisory openeuler.org
- patch openwall.com
- patch git.kernel.org