CVE-2026-63090

Medium

Elevated severity or exploit probability.

CVSS base

8.8 HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — probability of exploitation (30 days)

0.9%

58.9th percentile

CISA KEV

Not listed

Weakness / dates

CWE-122

Published 2026-07-20 · modified 2026-07-30

CVSS breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	L	Low
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	H	High
Integrity	H	High
Availability	H	High

Timeline

2026-07-20 — Published (NVD)
2026-07-30 — Last modified (NVD)

Description

ProFTPD before 1.3.9c and 1.3.10rc3 contains a heap-based buffer overflow vulnerability in the mod_sftp module that allows authenticated low-privilege attackers to achieve arbitrary code execution by sending crafted SFTP packet fragments exceeding the 16 KB reassembly buffer in the fxp.c component. Attackers can supply oversized fragments to trigger an incorrectly conditioned reallocation, corrupt pool freelist metadata, overwrite the root_fs BSS global pointer to reference a fake filesystem struct, and redirect pr_fsio_stat() to system() via a crafted RENAME request.

Affected

proftpd

References

Official: NVD · CVE.org