CVE-2026-63090

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.

References

https://www.vulncheck.com/advisories/proftpd-mod-sftp-heap-buffer-overflow-via-sftp-packet-reassembly

https://github.com/proftpd/proftpd/releases/tag/v1.3.9c

https://github.com/proftpd/proftpd/releases/tag/v1.3.10rc3-3

https://github.com/proftpd/proftpd/issues/2190

https://github.com/proftpd/proftpd/commit/4ee8701bcf425f11b3b2116e634ff3e655d918b1

https://github.com/proftpd/proftpd/blob/master/RELEASE_NOTES

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4