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CVE-2026-63090

ProFTPD mod_sftp Heap Buffer Overflow via SFTP Packet Reassembly

Published: Jul 20, 2026Updated: Jul 30, 2026 Sources: CVE List NVDCWE-122
8.8HIGH
NVD MITRE
EPSS Score
0.5%
Top 59.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-122

Affected Products

proftpd
oss-projectaka proftpd-dfsg
proftpdOn-prem
Networking Infrastructure / network-management

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Privilege Escalation
View detailed technique mapping

References

https://github.com/proftpd/proftpd/blob/master/RELEASE_NOTES
github.com
https://github.com/proftpd/proftpd/releases/tag/v1.3.10rc3-3
github.com
https://github.com/proftpd/proftpd/releases/tag/v1.3.9c
github.com
and 3 more references View all →

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