Every CVE Search/ Get API key

CVE-2026-63447

Suricata ftp: crafted FTP traffic can cause quadratic CPU consumption

7.5 HighFix available

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
None
Integrity
None
Availability
High

Exploit likelihood

0.63%Up 0.3 points since Sep 19, 2026
90%50%10%1%

What each source reports

CVE List Score used 7.5

Suricata ftp: crafted FTP traffic can cause quadratic CPU consumption

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.

Record
CVE-2026-63447
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness
CWE-407
Updated
2026-11-02
EUVDEUVD-2026-83394 7.5

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.

Record
EUVD-2026-83394
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated
2026-11-02
NVD 7.5

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.

Record
CVE-2026-63447
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness
CWE-407
Updated
2026-11-02
OSV 7.5

Suricata ftp: crafted FTP traffic can cause quadratic CPU consumption

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.

Record
CVE-2026-63447
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness
CWE-407
Updated
2026-11-02
OSVDEBIAN-CVE-2026-63447 7.5

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.

Record
DEBIAN-CVE-2026-63447
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated
2026-11-02
OSVUBUNTU-CVE-2026-63447 7.5

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.

Record
UBUNTU-CVE-2026-63447
CVSS 3.1
7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated
2026-11-02

Affected products

Affected packages

Affected packages
PackageAffectedFixed
suricata
Debian:13
All versions, plus listed versions
1:7.0.10-11:7.0.10-1+deb13u11:7.0.10-1+deb13u21:7.0.10-1+deb13u31:7.0.10-1+deb13u4
Show 24 moreShow less
1:7.0.11-11:7.0.11-1~bpo13+11:8.0.0-1~exp11:8.0.0-1~exp21:8.0.0-1~exp41:8.0.0-1~exp51:8.0.1-11:8.0.1-21:8.0.1-31:8.0.1-3~bpo13+11:8.0.2-11:8.0.2-1~bpo13+11:8.0.3-11:8.0.3-1~bpo13+11:8.0.3-2~exp11:8.0.4-11:8.0.4-1~bpo13+11:8.0.5-11:8.0.5-1~bpo13+11:8.0.6-11:8.0.6-1~bpo13+11:8.0.7-11:8.0.7-1~bpo13+11:8.0.7-2~exp1
None known
suricata
Debian:14
before 1:8.0.6-1, plus listed versions
1:7.0.10-11:7.0.11-11:7.0.11-1~bpo13+11:8.0.0-1~exp11:8.0.0-1~exp2
Show 16 moreShow less
1:8.0.0-1~exp41:8.0.0-1~exp51:8.0.1-11:8.0.1-21:8.0.1-31:8.0.1-3~bpo13+11:8.0.2-11:8.0.2-1~bpo13+11:8.0.3-11:8.0.3-1~bpo13+11:8.0.3-2~exp11:8.0.4-11:8.0.4-1~bpo13+11:8.0.5-11:8.0.5-1~bpo13+11:8.0.6-1~bpo13+1
1:8.0.6-1
suricata
Ubuntu:16.04:LTS
All versions, plus listed versions
2.0.8-1build12.0.9-12.0.10-12.0.10-22.0.11-13.0-1
None known
suricata
Ubuntu:18.04:LTS
All versions, plus listed versions
3.2-2ubuntu3
None known
suricata
Ubuntu:22.04:LTS
All versions, plus listed versions
1:6.0.4-21:6.0.4-3
None known
suricata
Ubuntu:24.04:LTS
All versions, plus listed versions
1:7.0.0-21:7.0.2-11:7.0.2-1build11:7.0.3-1build11:7.0.3-1build3
None known
suricata
Ubuntu:26.04:LTS
All versions, plus listed versions
1:7.0.10-11:8.0.1-3build11:8.0.2-11:8.0.2-1build11:8.0.3-1
None known

History

History
RecordedChangedSources
first indexedCVE List, EUVD, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-63447 is a high vulnerability (CVSS 7.5) in Oisf Suricata, published September 18, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.63%, the 50th percentile. Fixed in suricata 1:8.0.6-1.

References

Show 4 moreShow less
MoveEnter Open