High technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available
Distribution package intelligence
Ubuntu vendor package status
Canonical’s release and source-package findings are shown separately from local repository availability.
1 package state
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.
Ubuntu release
Source package
Vendor state
Fixed version
Evidence
Ubuntu 24.04 LTSnoble · standard archive
curl
Vendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.
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-2026-5773 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitycurl: libcurl: Wrong file transfer due to incorrect SMB connection reuse
96 known affected
The vendor explicitly identifies these products as affected by this CVE.
build-of-trustee/trustee-rhel9 as a component of Confidential Compute Attestation
confidential-compute-attestation-tech-preview/trustee-rhel9 as a component of Confidential Compute Attestation
openshift-sandboxed-containers/osc-operator-bundle as a component of Confidential Compute Attestation
openshift-sandboxed-containers/osc-podvm-builder-rhel9 as a component of Confidential Compute Attestation
openshift-sandboxed-containers/osc-podvm-payload-rhel9 as a component of Confidential Compute Attestation
openshift-sandboxed-containers/osc-rhel9-operator as a component of Confidential Compute Attestation
openshift-logging/cluster-logging-operator-bundle as a component of Logging Subsystem for Red Hat OpenShift
openshift-logging/cluster-logging-rhel9-operator as a component of Logging Subsystem for Red Hat OpenShift
openshift-logging/eventrouter-rhel9 as a component of Logging Subsystem for Red Hat OpenShift
openshift-logging/fluentd-rhel9 as a component of Logging Subsystem for Red Hat OpenShift
openshift-logging/log-file-metric-exporter-rhel9 as a component of Logging Subsystem for Red Hat OpenShift
openshift-logging/logging-view-plugin-rhel9 as a component of Logging Subsystem for Red Hat OpenShift
Summary
A flaw was found in libcurl. Due to a logical error in the connection reuse mechanism for SMB (Server Message Block) transfers, libcurl might reuse an existing SMB connection with a different share than intended. This vulnerability, categorized as CWE-488 (Exposure of Data Element to Wrong Session), could lead to the download of an incorrect file or the upload of a file to an unintended location when an application uses libcurl for SMB transfers.
Remediation
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
Optional official sources
National CERT insights ?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.
Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.
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-2026-29924
No EUVD known-exploited evidence
ENISA has published the identifier mapping but no EUVD description has been stored yet.
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
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days
High technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available
01
What, why and how
libcurl might in some circumstances reuse the wrong connection for SMB(S)
transfers.
libcurl features a pool of recent connections so that subsequent requests can
reuse an existing connection to avoid overhead.
When reusing a connection a range of criteria must be met. Due to a logical
error in the code, a network transfer operation that was requested by an
application could wrongfully reuse an existing SMB connection to the same
server that was using a different 'share' than the new subsequent transfer
should.
This could in unlucky situations lead to the download of the wrong file or the
upload of a file to the wrong place. When this happens, the same credentials
are used and the server name is the same.
What
libcurl might in some circumstances reuse the wrong connection for SMB(S)
transfers.
libcurl features a pool of recent connections so that subsequent requests can
reuse an existing connection to avoid overhead.
When reusing a connection a range of criteria must be met. Due to a logical
error in the code, a network transfer operation that was requested by an
application could wrongfully reuse an existing SMB connection to the same
server that was using a different 'share' than the new subsequent transfer
should.
This could in unlucky situations lead to the download of the wrong file or the
upload of a file to the wrong place. When this happens, the same credentials
are used and the server name is the same.
Why
The product does not sufficiently enforce boundaries between the states of different sessions, causing data to be provided to, or used by, the wrong session.
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
libcurl might in some circumstances reuse the wrong connection for SMB(S)
transfers.
libcurl features a pool of recent connections so that subsequent requests can
reuse an existing connection to avoid overhead.
When reusing a connection a range of criteria must be met. Due to a logical
error in the code, a network transfer operation that was requested by an
application could wrongfully reuse an existing SMB connection to the same
server that was using a different 'share' than the new subsequent transfer
should.
This could in unlucky situations lead to the download of the wrong file or the
upload of a file to the wrong place. When this happens, the same credentials
are used and the server name is the same.
Why
The product does not sufficiently enforce boundaries between the states of different sessions, causing data to be provided to, or used by, the wrong session.
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.Reference recorded
A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.
Likely attack path
a network path → Exposure of Data Element to Wrong Session → 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
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-488: Exposure of Data Element to Wrong Session. The product does not sufficiently enforce boundaries between the states of different sessions, causing data to be provided to, or used by, the wrong session.
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:N/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.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.INoneIntegrity impact: No direct loss is represented by this metric.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
Only matched European and national findings are included. Language selectors and unavailable sources are omitted.
ENISA EUVD · EUVD-2026-29924Official EUVD mapping
0 linked advisory records.
Official EUVD recordBSI · German · WID-SEC-W-2026-1307cURL: Mehrere Schwachstellen
Ein Angreifer kann mehrere Schwachstellen in cURL ausnutzen, um Sicherheitsvorkehrungen zu umgehen, vertrauliche Informationen offenzulegen oder Daten zu manipulieren.
Official advisoryCERT-FR · French · CERTFR-2026-AVI-1125Multiples vulnérabilités dans les produits VMware
Official advisoryCERT-FR · French · CERTFR-2026-AVI-1023Multiples vulnérabilités dans Tenable Security Center
De multiples vulnérabilités ont été découvertes dans Tenable Security Center. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, une élévation de privilèges et une injection SQL (SQLi).
Official advisoryCERT-FR · French · CERTFR-2026-AVI-0796Multiples vulnérabilités dans Tenable Identity Exposure
Official advisoryCERT-FR · French · CERTFR-2026-AVI-0514Multiples vulnérabilités dans Curl
De multiples vulnérabilités ont été découvertes dans Curl. Elles permettent à un attaquant de provoquer une atteinte à la confidentialité des données et un contournement de la politique de sécurité.
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
build-of-trustee/trustee-rhel9 as a component of Confidential Compute Attestation; confidential-compute-attestation-tech-preview/trustee-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-operator-bundle as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-podvm-builder-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-podvm-payload-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-rhel9-operator as a component of Confidential Compute Attestation; openshift-logging/cluster-logging-operator-bundle as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/cluster-logging-rhel9-operator as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/eventrouter-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/fluentd-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/log-file-metric-exporter-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/logging-view-plugin-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/vector-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; cargo as a component of Red Hat Enterprise Linux 10; clippy as a component of Red Hat Enterprise Linux 10; curl as a component of Red Hat Enterprise Linux 10; curl.src as a component of Red Hat Enterprise Linux 10; libcurl as a component of Red Hat Enterprise Linux 10; libcurl-devel as a component of Red Hat Enterprise Linux 10; libcurl-minimal as a component of Red Hat Enterprise Linux 10; rust-analyzer as a component of Red Hat Enterprise Linux 10; rust-debugger-common as a component of Red Hat Enterprise Linux 10; rust-doc as a component of Red Hat Enterprise Linux 10; rust-gdb as a component of Red Hat Enterprise Linux 10; rust-lldb as a component of Red Hat Enterprise Linux 10; rust-src as a component of Red Hat Enterprise Linux 10; rust-std-static as a component of Red Hat Enterprise Linux 10; rust-std-static-aarch64-unknown-none-softfloat as a component of Red Hat Enterprise Linux 10; rust-std-static-wasm32-unknown-unknown as a component of Red Hat Enterprise Linux 10; rust-std-static-wasm32-wasip1 as a component of Red Hat Enterprise Linux 10; and 66 more
Fixed
curl-main@aarch64 as a component of Red Hat Hardened Images; curl-main@src as a component of Red Hat Hardened Images; curl-main@x86_64 as a component of Red Hat Hardened Images
Action
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
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 13 May 2026 · Last source change 13 May 2026, 17:45 UTC · CWE-488 · Exposure of Data Element to Wrong Session
CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
EPSS source ?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-29924
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Affected versionsThe structured affected or fixed version information changed.
Before
build-of-trustee/trustee-rhel9 as a component of Confidential Compute Attestation; confidential-compute-attestation-tech-preview/trustee-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-operator-bundle as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-podvm-builder-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-podvm-payload-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-rhel9-operator as a component of Confidential Compute Attestation; openshift-logging/cluster-logging-operator-bundle as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/cluster-logging-rhel9-operator as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/eventrouter-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/fluentd-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/log-file-metric-exporter-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/logging-view-plugin-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/vector-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; cargo as a component of Red Hat Enterprise Linux 10; clippy as a component of Red Hat Enterprise Linux 10; curl as a component of Red Hat Enterprise Linux 10; curl.src as a component of Red Hat Enterprise Linux 10; libcurl as a component of Red Hat Enterprise Linux 10; libcurl-devel as a component of Red Hat Enterprise Linux 10; libcurl-minimal as a component of Red Hat Enterprise Linux 10; rust-analyzer as a component of Red Hat Enterprise Linux 10; rust-debugger-common as a component of Red Hat Enterprise Linux 10; rust-doc as a component of Red Hat Enterprise Linux 10; rust-gdb as a component of Red Hat Enterprise Linux 10; rust-lldb as a component of Red Hat Enterprise Linux 10; rust-src as a component of Red Hat Enterprise Linux 10; rust-std-static as a component of Red Hat Enterprise Linux 10; rust-std-static-aarch64-unknown-none-softfloat as a component of Red Hat Enterprise Linux 10; rust-std-static-wasm32-unknown-unknown as a component of Red Hat Enterprise Linux 10; rust-std-static-wasm32-wasip1 as a component of Red Hat Enterprise Linux 10; and 65 more · Fixed: curl-main@aarch64 as a component of Red Hat Hardened Images; curl-main@src as a component of Red Hat Hardened Images; curl-main@x86_64 as a component of Red Hat Hardened Images
After
build-of-trustee/trustee-rhel9 as a component of Confidential Compute Attestation; confidential-compute-attestation-tech-preview/trustee-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-operator-bundle as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-podvm-builder-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-podvm-payload-rhel9 as a component of Confidential Compute Attestation; openshift-sandboxed-containers/osc-rhel9-operator as a component of Confidential Compute Attestation; openshift-logging/cluster-logging-operator-bundle as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/cluster-logging-rhel9-operator as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/eventrouter-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/fluentd-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/log-file-metric-exporter-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/logging-view-plugin-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; openshift-logging/vector-rhel9 as a component of Logging Subsystem for Red Hat OpenShift; cargo as a component of Red Hat Enterprise Linux 10; clippy as a component of Red Hat Enterprise Linux 10; curl as a component of Red Hat Enterprise Linux 10; curl.src as a component of Red Hat Enterprise Linux 10; libcurl as a component of Red Hat Enterprise Linux 10; libcurl-devel as a component of Red Hat Enterprise Linux 10; libcurl-minimal as a component of Red Hat Enterprise Linux 10; rust-analyzer as a component of Red Hat Enterprise Linux 10; rust-debugger-common as a component of Red Hat Enterprise Linux 10; rust-doc as a component of Red Hat Enterprise Linux 10; rust-gdb as a component of Red Hat Enterprise Linux 10; rust-lldb as a component of Red Hat Enterprise Linux 10; rust-src as a component of Red Hat Enterprise Linux 10; rust-std-static as a component of Red Hat Enterprise Linux 10; rust-std-static-aarch64-unknown-none-softfloat as a component of Red Hat Enterprise Linux 10; rust-std-static-wasm32-unknown-unknown as a component of Red Hat Enterprise Linux 10; rust-std-static-wasm32-wasip1 as a component of Red Hat Enterprise Linux 10; and 66 more · Fixed: curl-main@aarch64 as a component of Red Hat Hardened Images; curl-main@src as a component of Red Hat Hardened Images; curl-main@x86_64 as a component of Red Hat Hardened Images
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.
CVE-2026-5773: wrong reuse of SMB connection | BlackTree
