CVE-2026-33711

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-33711", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-03-23T17:06:05.747Z", "datePublished": "2026-03-26T22:37:29.746Z", "dateUpdated": "2026-03-27T20:00:18.358Z"}, "containers": {"cna": {"title": "Incus vulnerable to local privilege escalation through VM screenshot path", "problemTypes": [{"descriptions": [{"cweId": "CWE-61", "lang": "en", "description": "CWE-61: UNIX Symbolic Link (Symlink) Following", "type": "CWE"}]}], "metrics": [{"cvssV4_0": {"attackVector": "LOCAL", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 4.7, "baseSeverity": "MEDIUM", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P", "version": "4.0"}}], "references": [{"name": "https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x"}], "affected": [{"vendor": "lxc", "product": "incus", "versions": [{"version": "< 6.23.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-03-26T22:37:29.746Z"}, "descriptions": [{"lang": "en", "value": "Incus is a system container and virtual machine manager. Incus provides an API to retrieve VM screenshots. That API relies on the use of a temporary file for QEMU to write the screenshot to which is then picked up and sent to the user prior to deletion. As versions prior to 6.23.0 use predictable paths under /tmp for this, an attacker with local access to the system can abuse this mechanism by creating their own symlinks ahead of time. On the vast majority of Linux systems, this will result in a \"Permission denied\" error when requesting a screenshot. That's because the Linux kernel has a security feature designed to block such attacks, `protected_symlinks`. On the rare systems with this purposefully disabled, it's then possible to trick Incus intro truncating and altering the mode and permissions of arbitrary files on the filesystem, leading to a potential denial of service or possible local privilege escalation. Version 6.23.0 fixes the issue."}], "source": {"advisory": "GHSA-q9vp-3wcg-8p4x", "discovery": "UNKNOWN"}}, "adp": [{"references": [{"url": "https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x", "tags": ["exploit"]}], "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-03-27T14:10:12.851754Z", "id": "CVE-2026-33711", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-03-27T20:00:18.358Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-33711", "role": "CISA Coordinator", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-03-27T14:10:12.851754Z"}}}], "references": [{"url": "https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x", "tags": ["exploit"]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-03-27T14:10:23.208Z"}}], "cna": {"title": "Incus vulnerable to local privilege escalation through VM screenshot path", "source": {"advisory": "GHSA-q9vp-3wcg-8p4x", "discovery": "UNKNOWN"}, "metrics": [{"cvssV4_0": {"version": "4.0", "baseScore": 4.7, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE"}}], "affected": [{"vendor": "lxc", "product": "incus", "versions": [{"status": "affected", "version": "< 6.23.0"}]}], "references": [{"url": "https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x", "name": "https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x", "tags": ["x_refsource_CONFIRM"]}], "descriptions": [{"lang": "en", "value": "Incus is a system container and virtual machine manager. Incus provides an API to retrieve VM screenshots. That API relies on the use of a temporary file for QEMU to write the screenshot to which is then picked up and sent to the user prior to deletion. As versions prior to 6.23.0 use predictable paths under /tmp for this, an attacker with local access to the system can abuse this mechanism by creating their own symlinks ahead of time. On the vast majority of Linux systems, this will result in a \"Permission denied\" error when requesting a screenshot. That's because the Linux kernel has a security feature designed to block such attacks, `protected_symlinks`. On the rare systems with this purposefully disabled, it's then possible to trick Incus intro truncating and altering the mode and permissions of arbitrary files on the filesystem, leading to a potential denial of service or possible local privilege escalation. Version 6.23.0 fixes the issue."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-61", "description": "CWE-61: UNIX Symbolic Link (Symlink) Following"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-03-26T22:37:29.746Z"}}}, "cveMetadata": {"cveId": "CVE-2026-33711", "state": "PUBLISHED", "dateUpdated": "2026-03-27T20:00:18.358Z", "dateReserved": "2026-03-23T17:06:05.747Z", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "datePublished": "2026-03-26T22:37:29.746Z", "assignerShortName": "GitHub_M"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"product": "incus", "vendor": "lxc", "versions": [{"status": "affected", "version": "< 6.23.0"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*", "matchCriteriaId": "CBE3ABCB-1D47-4A45-A09A-C9F609C53131", "versionEndExcluding": "6.23.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Incus is a system container and virtual machine manager. Incus provides an API to retrieve VM screenshots. That API relies on the use of a temporary file for QEMU to write the screenshot to which is then picked up and sent to the user prior to deletion. As versions prior to 6.23.0 use predictable paths under /tmp for this, an attacker with local access to the system can abuse this mechanism by creating their own symlinks ahead of time. On the vast majority of Linux systems, this will result in a \"Permission denied\" error when requesting a screenshot. That's because the Linux kernel has a security feature designed to block such attacks, `protected_symlinks`. On the rare systems with this purposefully disabled, it's then possible to trick Incus intro truncating and altering the mode and permissions of arbitrary files on the filesystem, leading to a potential denial of service or possible local privilege escalation. Version 6.23.0 fixes the issue."}, {"lang": "es", "value": "Incus es un gestor de contenedores de sistema y m\u00e1quinas virtuales. Incus proporciona una API para recuperar capturas de pantalla de la m\u00e1quina virtual. Esa API se basa en el uso de un archivo temporal para que QEMU escriba la captura de pantalla, la cual luego se recoge y se env\u00eda al usuario antes de su eliminaci\u00f3n. Dado que las versiones anteriores a la 6.23.0 utilizan rutas predecibles bajo /tmp para esto, un atacante con acceso local al sistema puede abusar de este mecanismo creando sus propios enlaces simb\u00f3licos con antelaci\u00f3n. En la gran mayor\u00eda de los sistemas Linux, esto resultar\u00e1 en un error de 'Permiso denegado' al solicitar una captura de pantalla. Esto se debe a que el kernel de Linux tiene una caracter\u00edstica de seguridad dise\u00f1ada para bloquear tales ataques, protected_symlinks. En los sistemas raros con esto deshabilitado a prop\u00f3sito, es entonces posible enga\u00f1ar a Incus para que trunque y altere el modo y los permisos de archivos arbitrarios en el sistema de archivos, lo que lleva a una potencial denegaci\u00f3n de servicio o posible escalada de privilegios local. La versi\u00f3n 6.23.0 corrige el problema."}], "id": "CVE-2026-33711", "lastModified": "2026-06-17T10:37:58.047", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "LOCAL", "availabilityRequirement": "NOT_DEFINED", "baseScore": 4.7, "baseSeverity": "MEDIUM", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "PROOF_OF_CONCEPT", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "LOW", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-33711", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-03-27T14:10:12.851754Z", "version": "2.0.3"}}]}, "published": "2026-03-26T23:16:20.423", "references": [{"source": "security-advisories@github.com", "tags": ["Exploit", "Vendor Advisory"], "url": "https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"], "url": "https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-61"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{"bugzilla": {"description": "incus: Incus: Local privilege escalation or denial of service via predictable temporary file paths", "id": "2452021", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2452021"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.8", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-59", "details": ["A flaw was found in Incus, a system container and virtual machine manager. A local attacker could exploit a vulnerability in the API responsible for retrieving VM screenshots. By creating symbolic links (symlinks) in predictable temporary file paths, an attacker could trick Incus into truncating and altering arbitrary files on the filesystem. This could lead to a denial of service or, in specific configurations where the `protected_symlinks` kernel security feature is disabled, a local privilege escalation."], "name": "CVE-2026-33711", "public_date": "2026-03-26T22:37:29Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-33711\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-33711\nhttps://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x"], "statement": "This Important flaw in Incus allows a local attacker to achieve denial of service or, under specific conditions, local privilege escalation. The vulnerability arises from predictable temporary file paths used during VM screenshot retrieval, enabling symlink attacks. On Red Hat Enterprise Linux, the `protected_symlinks` kernel security feature is enabled by default, which prevents the privilege escalation vector of this flaw.", "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.23.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "incus", "source": "cna", "vendor": "lxc"}, "product": "incus", "vendor": "lxc"}], "analysis": {"en": {"generated_at": "2026-03-30T21:07:16.246861+00:00", "value": {"mitigation_remediation": ["Upgrade Incus to version 6.23.0 or later", "Ensure the kernel\u2019s protected_symlinks feature is enabled to mitigate symlink attacks", "Restrict local user privileges that allow write access to Incus-specified temporary directories", "Monitor Incus logs for unexpected screenshot requests or permission errors"], "summary": {"action": "Patch Now", "impact": "Local Privilege Escalation"}, "threat_synthesis": {"affected_systems": "The affected product is Incus from the Linux Containers project. Versions earlier than 6.23.0 are vulnerable to this exploit. The changelog for 6.23.0 and later mitigates the issue by using non\u2011predictable temporary file paths.", "description_and_impact": "Incus, a system container and virtual machine manager, exposes an API that retrieves virtual machine screenshots. The API writes the image to a temporary file in a predictable location under /tmp before sending it back to the requester and deleting the file. When Incus versions prior to 6.23.0 are used, an attacker who can run commands locally can create a symlink in /tmp pointing to a file of the attacker\u2019s choice. If the kernel\u2019s protected_symlinks feature is disabled, Incus will follow the symlink, allowing the attacker to truncate the target file and alter its mode and ownership. This can lead to denial of service or local privilege escalation, as the attacker may gain unauthorized write access to arbitrary filesystem objects. The vulnerability involves path traversal weaknesses (CWE\u201159 and CWE\u201161).", "risk_and_exploitability": "The CVSS score of 4.7 indicates a moderate severity, and the EPSS score of less than 1% suggests that the likelihood of exploitation is low under current conditions. The vulnerability is not listed in the CISA KEV catalog. The attack requires local system access and the ability to create symlinks in the /tmp directory. It is inferred that the most probable attack vector is an authenticated local user who has write permissions in the Incus environment or the /tmp filesystem."}}}}, "created": "2026-03-27T08:31:30.209847+00:00", "updated": "2026-03-31T20:01:25.229365+00:00", "vendors": ["lxc", "lxc$PRODUCT$incus"]}