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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.93%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.93% probability · 59th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-122
- Affected
- proftpd/proftpd
- Source
- disclosure@vulncheck.com
References
- https://github.com/proftpd/proftpd/blob/master/RELEASE_NOTESRelease Notes
- https://github.com/proftpd/proftpd/commit/4ee8701bcf425f11b3b2116e634ff3e655d918b1Patch
- https://github.com/proftpd/proftpd/issues/2190Issue Tracking
- https://github.com/proftpd/proftpd/releases/tag/v1.3.10rc3-3Product, Release Notes
- https://github.com/proftpd/proftpd/releases/tag/v1.3.9cProduct, Release Notes
- https://www.vulncheck.com/advisories/proftpd-mod-sftp-heap-buffer-overflow-via-sftp-packet-reassemblyThird Party Advisory, Patch, Release Notes
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.