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 0.32% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-66079High confidence
RabbitMQ: Pre-auth AMQP 1.0 array32 zero-width element DoS
rabbitmq · rabbitmq-server
Official source article: GitHub GHSA-C66H-HF5J-8JF9 ↗. Check the applicable product and release in the original source.
8.2HighCVSS 4.0
Patch only the product branches with a verified fix
Fix availability varies by productHigh technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 120 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityHigh→Operational priority:High, 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 rabbitmq rabbitmq-server 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.
Remediation availability differs by product scope
Verified remediation exists for at least one product or source, but 120 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
- SUSE Product Security Team: 118 affected or under-investigation product states without a fixed product state in the same current advisory
- Debian Security Tracker: 2 affected package states with no published fix
Distribution package intelligence
5 package statesRelease-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.
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 2 affected package states 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 release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Debian trixietrixie · source | rabbitmq-server | Affected, no fix publishedDebian currently tracks this release as open. | Not published in this feed | Debian Security Tracker ↗Source updated 9 Oct 2026 |
| Debian bookwormbookworm · source | rabbitmq-server | Affected, no fix publishedDebian currently tracks this release as open. | Not published in this feed | Debian Security Tracker ↗Source updated 9 Oct 2026 |
| Debian forkyforky · source | rabbitmq-server | Vendor fix publishedDebian records a fixed source-package version for this release. | 4.3.0-2 | Debian Security Tracker ↗Source updated 9 Oct 2026 |
| Debian sidsid · source | rabbitmq-server | Vendor fix publishedDebian records a fixed source-package version for this release. | 4.3.0-2 | Debian Security Tracker ↗Source updated 9 Oct 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | rabbitmq-server | Under evaluationCanonical reports that the package might be affected and still needs evaluation or fixing. | Not published in this feed | Canonical Ubuntu Security ↗Source updated 8 Oct 2026 |
Direct vendor intelligence
2 currentAuthoritative 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.
CVE-2026-66079 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityrabbitmq-server: RabbitMQ: Denial of Service via AMQP 1.0 array32 parsing
The vendor explicitly identifies these products as affected by this CVE.
- rabbitmq-server4.2.src as a component of Red Hat Hardened Images
- Summary
- A flaw was found in RabbitMQ. An unauthenticated network attacker can exploit an issue in the AMQP 1.0 listener by sending a specially crafted ~19-byte frame. This causes the system to attempt to build a list of approximately 4 billion empty elements, exhausting heap memory and terminating the Erlang Virtual Machine (VM). This results in a complete denial of service for all tenants and protocols on the affected node.
- Remediation
- For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
CVE-2026-66079 · CSAF 2.0 · revision 2 · interimSUSE Product Security TeamCVE-2026-66079
The vendor explicitly identifies these products as affected by this CVE.
- erlang-rabbitmq-client as component of SUSE Linux Enterprise High Performance Computing 15 SP2
- rabbitmq-server as component of SUSE Linux Enterprise High Performance Computing 15 SP2
- rabbitmq-server-plugins as component of SUSE Linux Enterprise High Performance Computing 15 SP2
- erlang-rabbitmq-client as component of SUSE Linux Enterprise High Performance Computing 15 SP3
- rabbitmq-server as component of SUSE Linux Enterprise High Performance Computing 15 SP3
- rabbitmq-server-plugins as component of SUSE Linux Enterprise High Performance Computing 15 SP3
- erlang-rabbitmq-client as component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
- rabbitmq-server as component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
- rabbitmq-server-plugins as component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
- erlang-rabbitmq-client as component of SUSE Linux Enterprise High Performance Computing 15 SP4
- rabbitmq-server as component of SUSE Linux Enterprise High Performance Computing 15 SP4
- rabbitmq-server-plugins as component of SUSE Linux Enterprise High Performance Computing 15 SP4
- Summary
- RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6, parse_array_primitive/2 for constructor 0x45 (list0) returns an element with byte-width B = 0. The enclosing array32 parser at line 148 reads a 4-byte Count from the wire and loops Count times consuming B bytes each , with B = 0, no input is consumed and the loop builds a list of Count empty elements bounded only by the 32-bit field. The SASL-mechanisms / SASL-init frame is parsed by amqp10_framing:decode_bin/1 from rabbit_amqp_reader.erl:412 before authentication completes. The pre-auth incoming_max_frame_size (default 8192 bytes) caps the frame, not the Count field, so a 19-byte payload with Count = 0xFFFFFFFF is accepted. No max_heap_size is set on the reader process. An unauthenticated network attacker can crash any RabbitMQ node that has the AMQP 1.0 listener enabled (default port 5672) by sending a single ~19-byte frame. The reader process attempts to build a list of ~4 billion empty elements, exhausting heap memory and terminating the Erlang VM. All tenants and protocols on the node lose service. Preconditions include Network reachability to the AMQP listener (port 5672, enabled by default) No authentication required. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
- Remediation
- No remediation text is recorded.
High technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 120 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Fix availability varies by product01
What, why and how
RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6, parse_array_primitive/2 for constructor 0x45 (list0) returns an element with byte-width B = 0. The enclosing array32 parser at line 148 reads a 4-byte Count from the wire and loops Count times consuming B bytes each , with B = 0, no input is consumed and the loop builds a list of Count empty elements bounded only by the 32-bit field. The SASL-mechanisms / SASL-init frame is parsed by amqp10_framing:decode_bin/1 from rabbit_amqp_reader.erl:412 before authentication completes. The pre-auth incoming_max_frame_size (default 8192 bytes) caps the frame, not the Count field, so a 19-byte payload with Count = 0xFFFFFFFF is accepted. No max_heap_size is set on the reader process. An unauthenticated network attacker can crash any RabbitMQ node that has the AMQP 1.0 listener enabled (default port 5672) by sending a single ~19-byte frame. The reader process attempts to build a list of ~4 billion empty elements, exhausting heap memory and terminating the Erlang VM. All tenants and protocols on the node lose service. Preconditions include Network reachability to the AMQP listener (port 5672, enabled by default) No authentication required. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
What
RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6, parse_array_primitive/2 for constructor 0x45 (list0) returns an element with byte-width B = 0. The enclosing array32 parser at line 148 reads a 4-byte Count from the wire and loops Count times consuming B bytes each , with B = 0, no input is consumed and the loop builds a list of Count empty elements bounded only by the 32-bit field. The SASL-mechanisms / SASL-init frame is parsed by amqp10_framing:decode_bin/1 from rabbit_amqp_reader.erl:412 before authentication completes. The pre-auth incoming_max_frame_size (default 8192 bytes) caps the frame, not the Count field, so a 19-byte payload with Count = 0xFFFFFFFF is accepted. No max_heap_size is set on the reader process. An unauthenticated network attacker can crash any RabbitMQ node that has the AMQP 1.0 listener enabled (default port 5672) by sending a single ~19-byte frame. The reader process attempts to build a list of ~4 billion empty elements, exhausting heap memory and terminating the Erlang VM. All tenants and protocols on the node lose service. Preconditions include Network reachability to the AMQP listener (port 5672, enabled by default) No authentication required. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
Why
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.
What
RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6, parse_array_primitive/2 for constructor 0x45 (list0) returns an element with byte-width B = 0. The enclosing array32 parser at line 148 reads a 4-byte Count from the wire and loops Count times consuming B bytes each , with B = 0, no input is consumed and the loop builds a list of Count empty elements bounded only by the 32-bit field. The SASL-mechanisms / SASL-init frame is parsed by amqp10_framing:decode_bin/1 from rabbit_amqp_reader.erl:412 before authentication completes. The pre-auth incoming_max_frame_size (default 8192 bytes) caps the frame, not the Count field, so a 19-byte payload with Count = 0xFFFFFFFF is accepted. No max_heap_size is set on the reader process. An unauthenticated network attacker can crash any RabbitMQ node that has the AMQP 1.0 listener enabled (default port 5672) by sending a single ~19-byte frame. The reader process attempts to build a list of ~4 billion empty elements, exhausting heap memory and terminating the Erlang VM. All tenants and protocols on the node lose service. Preconditions include Network reachability to the AMQP listener (port 5672, enabled by default) No authentication required. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
Why
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.
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 → Allocation of Resources Without Limits or Throttling → disrupt the affected service
- Attack surface
- Network
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Not a CVSS 4.0 base metric
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-770 ↗
CWE-770: Allocation of Resources Without Limits or Throttling. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCommon Vulnerability Scoring System 4.0: 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.ATPresentAttack requirements: A particular deployment or execution condition must be present.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.VCNoneVulnerable-system confidentiality: No direct loss is represented by this metric.VINoneVulnerable-system integrity: No direct loss is represented by this metric.VAHighVulnerable-system availability: A successful attack can cause a major loss.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: 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.
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
- Fixed
- 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.
04
Evidence and provenance
Published 23 Sept 2026 · Last source change 29 Sept 2026, 02:12 UTC · CWE-770 · Allocation of Resources Without Limits or Throttling
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-2026-85627
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD enrichment underway
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: removed remediation: access.redhat.com/CVE-2026-66079.CNA ↗
- Before
- remediation: access.redhat.com/CVE-2026-66079
- After
- no authoritative guidance recorded
- Affected versionsThe structured affected or fixed version information changed.CNA ↗
- Before
- rabbitmq-server: >= 3.13.0, < 3.13.15, >= 4.0.0, < 4.0.20, >= 4.1.0, < 4.1.11, >= 4.2.0, < 4.2.6 · Fixed: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
- After
- rabbitmq-server: >= 3.13.0, < 3.13.15, >= 4.0.0, < 4.0.20, >= 4.1.0, < 4.1.11, >= 4.2.0, < 4.2.6 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- Remediation statusRemediation status changed from Patch available to Awaiting fix.CNA ↗
- Before
- Patch available
- After
- Awaiting fix
- Affected versionsThe structured affected or fixed version information changed.Red Hat Product Security ↗
- Before
- rabbitmq-server: >= 3.13.0, < 3.13.15, >= 4.0.0, < 4.0.20, >= 4.1.0, < 4.1.11, >= 4.2.0, < 4.2.6 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- After
- rabbitmq-server: >= 3.13.0, < 3.13.15, >= 4.0.0, < 4.0.20, >= 4.1.0, < 4.1.11, >= 4.2.0, < 4.2.6 · Fixed: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
- Remediation statusRemediation status changed from Awaiting fix to Patch available.Red Hat Product Security ↗
- Before
- Awaiting fix
- After
- Patch available
- Vendor guidanceAuthoritative vendor guidance changed from remediation: access.redhat.com/CVE-2026-66079 to remediation: access.redhat.com/CVE-2026-66079.Red Hat Product Security ↗
- Before
- remediation: access.redhat.com/CVE-2026-66079
- After
- remediation: access.redhat.com/CVE-2026-66079
- Remediation statusRemediation status changed from Mitigation available to Patch available.Red Hat Product Security ↗
- Before
- Mitigation available
- After
- Patch available
- Affected versionsThe structured affected or fixed version information changed.Red Hat Product Security ↗
- Before
- rabbitmq-server4.2.src as a component of Red Hat Hardened Images; rabbitmq-server4.3.src as a component of Red Hat Hardened Images; rabbitmq-server.src as a component of Red Hat OpenStack Platform 18.0
- After
- rabbitmq-server4.2.src as a component of Red Hat Hardened Images · Fixed: rabbitmq-server4.3-0:4.3.6-1.hum1@aarch64 as a component of Red Hat Hardened Images; rabbitmq-server4.3-0:4.3.6-1.hum1@src as a component of Red Hat Hardened Images; rabbitmq-server4.3-0:4.3.6-1.hum1@x86_64 as a component of Red Hat Hardened Images
- ENISA EUVD mappingEUVD-2026-85627 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-85627"}
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
CVE published
Fixed release recorded from official guidance
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.