Security readout for executives and security teams
Plain-English summary
CVE-2021-46179 is a denial-of-service issue in UPX before 4.0.0. A specially crafted file can trigger an assertion failure when UPX reads input. The business risk is disruption to systems or pipelines that automatically process untrusted files with UPX, not data theft or code execution based on the provided sources.
Executive priority
Treat this as a focused operational resilience issue. Prioritize environments where UPX processes untrusted files automatically, especially if crashes could interrupt security analysis, CI, or customer-facing file services.
Technical view
The CVE describes a reachable assertion in UPX before 4.0.0, involving crafted input passed to the readx function. Public data provided does not include CVSS, CWE mapping, detailed affected platform data, or a vendor advisory beyond the referenced GitHub issue.
Likely exposure
Exposure is most likely where UPX is installed in file analysis, malware triage, unpacking, build, or scanning workflows that process files from untrusted sources.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation. The documented impact is denial of service through crafted file input, with no cited evidence of remote code execution.
Researcher notes
Evidence is limited: no CVSS, CWE, exploit status, or detailed advisory text is included. Analysis should stay scoped to reachable assertion denial of service in UPX before 4.0.0.
Mitigation direction
- Inventory systems and pipelines that run UPX against user-supplied or untrusted files.
- Upgrade UPX deployments to version 4.0.0 or later where applicable.
- Check the referenced UPX issue and CVE record for vendor-specific guidance.
- Isolate automated file-processing workers that use UPX from critical services.
- Apply resource limits and restart supervision around UPX-based processing jobs.
Validation and detection
- Confirm installed UPX versions across developer workstations, CI, scanners, and analysis systems.
- Identify workflows where UPX receives files from external or low-trust sources.
- Review recent processing logs for UPX assertion failures or unexplained worker crashes.
- Verify upgraded systems continue normal unpacking and analysis workflows.
- Document whether UPX is internet-adjacent, batch-only, or isolated.
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.
CVE-2021-46179 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://github.com/upx/upx/issues/545CVE reference
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.