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Full vulnerability report · 2026
CVE-2026-63450High confidence

Suricata ftp: RETR/STOR before PORT/PASV can disable further IDS app-layer detection

OISF · suricata

Official source article: GitHub GHSA-56WX-7HQH-WFGR ↗. Check the applicable product and release in the original source.

3.7LowCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

Low technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityLowOperational priority:Low, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 0.25% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs OISF suricata and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: No default targetRemediation target: Normal maintenance

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

4 package states
Package result overrides the generic status

BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 1 affected package state shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.

Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcesuricataAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcesuricataVendor fix publishedDebian records a fixed source-package version for this release.1:8.0.6-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcesuricataVendor fix publishedDebian records a fixed source-package version for this release.1:8.0.6-1Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivesuricataUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical Ubuntu Security ↗Source updated 4 Oct 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2026-63450 · CSAF 2.0 · revision 3 · finalRed Hat Product SecuritySuricata: Suricata: Security bypass via FTP command sequence mishandling
1 known not affected

The vendor explicitly states that these products are not affected by this CVE.

  • All currently supported Red Hat products
Summary
A flaw was found in Suricata, a network Intrusion Detection System (IDS) and Intrusion Prevention System (IPS). A remote attacker can exploit a vulnerability in the FTP parser where sending a `RETR` or `STOR` command before `PORT` or `PASV` negotiation is incorrectly treated as a fatal error. This error disables further FTP application-layer parsing for the duration of the TCP connection, allowing subsequent commands to bypass detection rules and logging in IDS mode, or causing the flow to be dropped in IPS mode. This can lead to a security bypass, enabling attackers to evade security monitoring.
Remediation
No remediation text is recorded.
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-83387

No EUVD known-exploited evidence

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 8.0.6, the FTP parser in src/app-layer-ftp.c treats a RETR or STOR command sent before PORT or PASV negotiation as a fatal application-layer error instead of a recoverable protocol event. The fatal state disables FTP application-layer parsing for the remainder of the TCP flow, so later commands can evade parser-dependent rules and logging; IPS mode instead drops the flow. This issue is fixed in version 8.0.6.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
3.7 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

Low technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 8.0.6, the FTP parser in src/app-layer-ftp.c treats a RETR or STOR command sent before PORT or PASV negotiation as a fatal application-layer error instead of a recoverable protocol event. The fatal state disables FTP application-layer parsing for the remainder of the TCP flow, so later commands can evade parser-dependent rules and logging; IPS mode instead drops the flow. This issue is fixed in version 8.0.6.

What

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 8.0.6, the FTP parser in src/app-layer-ftp.c treats a RETR or STOR command sent before PORT or PASV negotiation as a fatal application-layer error instead of a recoverable protocol event. The fatal state disables FTP application-layer parsing for the remainder of the TCP flow, so later commands can evade parser-dependent rules and logging; IPS mode instead drops the flow. This issue is fixed in version 8.0.6.

Why

The product does not handle or incorrectly handles an exceptional condition.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 8.0.6, the FTP parser in src/app-layer-ftp.c treats a RETR or STOR command sent before PORT or PASV negotiation as a fatal application-layer error instead of a recoverable protocol event. The fatal state disables FTP application-layer parsing for the remainder of the TCP flow, so later commands can evade parser-dependent rules and logging; IPS mode instead drops the flow. This issue is fixed in version 8.0.6.

Why

The product does not handle or incorrectly handles an exceptional condition.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Improper Handling of Exceptional Conditions → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-755 ↗

CWE-755: Improper Handling of Exceptional Conditions. The product does not handle or incorrectly handles an exceptional condition.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.ILowIntegrity impact: A successful attack can cause a limited loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-755
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2026-83387Official EUVD mapping

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 8.0.6, the FTP parser in src/app-layer-ftp.c treats a RETR or STOR command sent before PORT or PASV negotiation as a fatal application-layer error instead of a recoverable protocol event. The fatal state disables FTP application-layer parsing for the remainder of the TCP flow, so later commands can evade parser-dependent rules and logging; IPS mode instead drops the flow. This issue is fixed in version 8.0.6.

Official EUVD record ↗
JVN iPedia · Japanese · JVNDB-2026-035944oisfのsuricataにおける例外的な状態の処理に関する脆弱性

Suricataは、ネットワーク侵入検知システム（IDS）、侵入防止システム（IPS）、およびネットワークセキュリティ監視エンジンです。バージョン8.0.6より前では、src/app-layer-ftp.c内のFTPパーサーが、PORTまたはPASVのネゴシエーション前に送信されたRETRまたはSTORコマンドを、回復可能なプロトコルイベントとしてではなく致命的なアプリケーションレイヤーエラーとして扱っていました。この致命的な状態が原因で、TCPフローの残りの時間にわたってFTPアプリケーションレイヤーの解析が無効となり、後続のコマンドがパーサー依存のルールやログ記録を回避できるようになっていました。一方、IPSモードではこのフローを遮断します。この問題はバージョン8.0.6で修正されました。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix availability varies by product
Affected
suricata: < 8.0.6
Fixed
8.0.6.
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
Official vendor articles2 stored documents

Linked articles are downloaded and versioned as source evidence. A CVE mention or approved update relationship does not, by itself, verify a fix for every product branch.

04

Evidence and provenance

Published 18 Sept 2026 · Last source change 23 Sept 2026, 19:45 UTC · CWE-755 · Improper Handling of Exceptional Conditions

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-09-19
European sourceENISA EUVD · EUVD-2026-83387
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Vendor guidanceAuthoritative vendor guidance changed: added patch: github.com/15704; added patch: github.com/52490b8c26909772801afed98df63a6d62f3af18; removed remediation: github.com/GHSA-56wx-7hqh-wfgr; 3 further additions.
    Before
    remediation: github.com/GHSA-56wx-7hqh-wfgr
    After
    patch: github.com/15704 · patch: github.com/52490b8c26909772801afed98df63a6d62f3af18 · patch: github.com/feb0ff91159cea474a983adf92e4b56fb16e4ffc · 2 more references
    security-advisories@github.com ↗
  2. ENISA EUVD mappingEUVD-2026-83387 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2026-83387"}
    ENISA EUVD ↗
  3. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2026-83387↗Vendor CSAF · Red Hat Product Security↗CVE authority or vendor reference · GitHub GHSA-56WX-7HQH-WFGR↗Patch or update reference↗Patch or update reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-63450 · cve.blacktree.nl