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 1.45% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-6721High confidence
Multiple Vulnerabilities in IBM Concert Software
IBM · Concert
9.8CriticalCVSS 3.1
Within 72 hours
Patch availableCritical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityCritical→Operational priority:Critical, unchanged from published severity.unchanged
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
- Confirm that the asset runs IBM Concert and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.
Patch available01
What, why and how
IBM Concert 1.0.0 through 3.0.0 allows an unauthenticated remote attacker can supply specially crafted input that is incorporated into OS commands, resulting in arbitrary command execution on the underlying system. Successful exploitation allows remote code execution with the privileges of the affected application.
What
IBM Concert 1.0.0 through 3.0.0 allows an unauthenticated remote attacker can supply specially crafted input that is incorporated into OS commands, resulting in arbitrary command execution on the underlying system. Successful exploitation allows remote code execution with the privileges of the affected application.
Why
Untrusted input is incorporated into an operating-system command without safe parameter handling.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may execute code or commands in the affected security context.
What
IBM Concert 1.0.0 through 3.0.0 allows an unauthenticated remote attacker can supply specially crafted input that is incorporated into OS commands, resulting in arbitrary command execution on the underlying system. Successful exploitation allows remote code execution with the privileges of the affected application.
Why
Untrusted input is incorporated into an operating-system command without safe parameter handling.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may execute code or commands in the affected security context.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.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 None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.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 Neutralization of Special Elements used in an OS Command ('OS Command Injection') → execute code or commands in the affected security context
- Attack surface
- Network
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- 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-78 ↗
CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection'). The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.
- 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:L/PR:N/UI:N/S:U/C:H/I:H/A:HCommon 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.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.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.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.- Post-exploitation / living off the land
- After compromise, an attacker may use built-in shells, scripting engines, scheduled tasks and native network utilities for discovery, persistence or movement. This is a plausible LoTL path, not evidence that it has occurred for every attack.
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. - Patch available
- Affected
- Concert: 1.0.0 ≤ 3.0.0
- Fixed
- IBM strongly recommends addressing the vulnerability now by upgrading to IBM Concert Software 3.0.1.1
- Download IBM Concert Software 3.0.0 from Container software library section of IBM Entitled Registry ( ICR https://myibm.ibm.com/products-services/containerlibrary ) and follow installation instructions https://www.ibm.com/docs/en/concert depending on the type of deployment.
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- 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 articles1 stored document
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.
- Security Bulletin: Multiple Vulnerabilities in IBM Concert Software →Original publisher ↗Searchable text snapshot · Captured 28 Sep 2026IBM Support No results were found for your search query. Tips To return expected results, you can: Reduce the number of search terms. Each term you use focuses the search further. Check your spelling. A single misspelled or incorrectly typed term can change your result. Try substituting synonyms for your original ter
04
Evidence and provenance
Published 23 Sept 2026 · Last source change 25 Sept 2026, 03:55 UTC · CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-09-24
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-85661
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
View recent updates ↗What changed after publication
- Vendor guidanceAuthoritative vendor guidance changed: added vendor advisory: ibm.com/7288830.psirt@us.ibm.com ↗
- Before
- remediation: ibm.com/7288830
- After
- remediation: ibm.com/7288830 · vendor advisory: ibm.com/7288830
- ENISA EUVD mappingEUVD-2026-85661 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-85661"}
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
CVE published
Fixed release or patch reference recorded
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.