UNIT 42
Copy Fail: What You Need to Know About the Most Severe Linux Threat in Years
HIGH Linux CVE-2026-31431 Ubuntu kernel copy-fail
Strategic summary
Copy Fail enables local privilege escalation by manipulating the in-memory cache of privileged binaries without modifying on-disk files, bypassing integrity checks.
Relevance for you
Critical Linux kernel vulnerability affecting Ubuntu systems; immediate patching and impact assessment required for production Ubuntu 24.04 LTS deployments.
Mentioned CVEs
Risk score
100
- cvss base
- 78.00
- kev bonus
- 0.00
- epss bonus
- 0.00
- poc bonus
- 0.00
- raw before weight
- 78.00
- industry weight
- 1.30
- freshness factor
- 1.00
- days old
- 0.00
Path: operational
MITRE ATT&CK mapping
1 TTP Recon
Resource Dev
Initial Access
Execution
Persistence
Priv. Escal.
Def. Evasion
Cred. Access
Discovery
Lateral Mov.
Collection
C2
Exfiltration
Impact
Other
T1068 Procedure details
| Technique | Tactic | Procedure | Conf. | Source |
|---|---|---|---|---|
| T1068 | Technique T1068 explicitly referenced in source: Unit 42 | high | primary |