CVE-2026-63090

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/proftpd/proftpd/blob/master/RELEASE_NOTES	Release Notes
https://github.com/proftpd/proftpd/commit/4ee8701bcf425f11b3b2116e634ff3e655d918b1	Patch
https://github.com/proftpd/proftpd/issues/2190	Issue Tracking
https://github.com/proftpd/proftpd/releases/tag/v1.3.10rc3-3	Product Release Notes
https://github.com/proftpd/proftpd/releases/tag/v1.3.9c	Product Release Notes
https://www.vulncheck.com/advisories/proftpd-mod-sftp-heap-buffer-overflow-via-sftp-packet-reassembly	Third Party Advisory Patch Release Notes

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:proftpd:proftpd::::::::
	cpe:2.3:a:proftpd:proftpd:1.3.10:rc1::::::
	cpe:2.3:a:proftpd:proftpd:1.3.10:rc2::::::

History

No history.

Information

Published : 2026-07-20 15:16

Updated : 2026-07-30 17:19

NVD link : CVE-2026-63090

Mitre link : CVE-2026-63090

CVE.ORG link : CVE-2026-63090

JSON object : View

Products Affected

proftpd

proftpd

CWE

CWE-122

Heap-based Buffer Overflow

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