Buffer overflow in Gnu Grub2

CVE-2020-14309

There's an issue with grub2 in all versions before 2.06 when handling squashfs filesystems containing a symbolic link with name length of UINT32 bytes in size. The name size leads to an arithmetic overflow leading to a zero-size allocation further causing a heap-based buffer overflow with attacker controlled data.

Vulnerability class: Integer Overflow

EPSS: 0.005 (38.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.7 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-14309?
CVE-2020-14309 is a medium-severity vulnerability in Gnu Grub2, classified under Integer Overflow or Wraparound. CVSS score: 6.7/10. Published 2020-07-30.
How severe is CVE-2020-14309?
Medium severity. CVSS v3 base score is 6.7 out of 10.
Is CVE-2020-14309 known to be exploited?
26 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.