OverlayFS userns capability privesc (CVE-2021-3493)

Aynı bug/CVE: bkz. canonical overlayfs privilege escalation (CVE-2021-3493).

Mechanism

Bu not, canonical ile aynı root cause'u tarif eder: Ubuntu'nun FS_USERNS_MOUNT patch'i + capability re-validation eksikliği. Tam mekanizma için bkz. overlayfs privilege escalation (CVE-2021-3493).

Walkthrough

Tam walkthrough canonical not'ta: overlayfs privilege escalation (CVE-2021-3493).

References

• CVE-2021-3493 Ubuntu overlayfs analysis (terenceli)
• briskets/CVE-2021-3493 PoC
• NVD - CVE-2021-3493