Security readout for executives and security teams
This CVE describes a Linux kernel memory corruption flaw in old virtual terminal font-setting ioctl handling. Affected openEuler kernel builds before 5.10.127 are listed. The sources do not provide CVSS scoring, active exploitation evidence, or detailed impact beyond out-of-bounds kernel memory writes. Exposure is most plausible on Linux systems running affected downstream kernels with virtual terminal font ioctl support, especially openEuler kernel versions below 5.10.127. Other distributions may have shipped fixes through their own kernel advisories, as indicated by the Debian LTS update reference. Treat this as a kernel patching item for exposed Linux fleets, not as an emergency internet-facing incident based on available evidence. Prioritize systems on affected openEuler kernels and standardize remediation through normal kernel update and reboot processes. Mitigation focus: Upgrade affected openEuler kernels to 5.10.127 or a vendor-fixed later build.; Apply relevant downstream kernel security updates for non-openEuler distributions.; Reboot systems so the fixed kernel is actually running..
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
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Open ATT&CK lookupCVE-2021-33656 mapping review
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Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/releases/5.10.127/vt-drop-old-font-ioctls.patchCVE reference · x_refsource_MISC
- https://www.openeuler.org/en/security/cve/detail.html?id=CVE-2021-33656&packageName=kernelCVE reference · x_refsource_MISC
- [debian-lts-announce] 20221002 [SECURITY] [DLA 3131-1] linux security updateCVE reference · mailing-list, x_refsource_MLIST
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Out-of-bounds Write
Out-of-bounds Write represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.