Security readout for executives and security teams
Plain-English summary
This issue affects TianoCore EDK II firmware code, specifically an LZMA decompression information function. A heap overflow can create firmware-level reliability or security risk, but the provided sources do not include CVSS, exploit status, downstream vendors, or a named fix.
Executive priority
Prioritize identification over emergency response. Firmware issues can be high-impact, but current evidence lacks severity, exploitation, and downstream product mapping. Ask platform and firmware suppliers for exposure confirmation.
Technical view
CVE-2021-28211 is a CWE-122 heap-based buffer overflow in LzmaUefiDecompressGetInfo in TianoCore EDK II, listed against edk2-stable202008. The source bundle gives only a short description and Bugzilla reference, so impact conditions, attack prerequisites, and remediation details remain under-specified.
Likely exposure
Exposure is most likely in firmware projects, products, or forks using TianoCore EDK II edk2-stable202008 with the affected LZMA decompression code. Downstream product exposure is not identified in the provided sources.
Exploitation context
The source bundle does not show CISA KEV listing, active exploitation, public exploit details, or exploitation prerequisites. Treat exploitation evidence as incomplete, not absent.
Researcher notes
The available record is sparse: title, description, CWE-122, one affected version, and a TianoCore Bugzilla reference. Avoid assuming affected OEM products, exploitability, or fixes without vendor confirmation.
Mitigation direction
- Check TianoCore Bugzilla issue 1816 and vendor guidance for the authoritative remediation path.
- Inventory firmware codebases and supplier SBOMs for TianoCore EDK II edk2-stable202008.
- Request firmware vendor confirmation if EDK II provenance is unclear.
- Use only vendor-supported firmware updates when remediation becomes available.
Validation and detection
- Confirm whether firmware builds include TianoCore EDK II edk2-stable202008.
- Check whether the LZMA UEFI decompression component is present in affected builds.
- Review supplier advisories or SBOMs for CVE-2021-28211 references.
- Document systems where firmware lineage cannot be confirmed.
Public sources used
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
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-122: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-28211 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
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://bugzilla.tianocore.org/show_bug.cgi?id=1816CVE reference · x_refsource_MISC
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.
Heap-based Buffer Overflow
Heap-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.