{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-28356", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-02-26T18:38:13.890Z", "datePublished": "2026-03-12T16:45:01.070Z", "dateUpdated": "2026-03-13T16:29:28.768Z"}, "containers": {"cna": {"title": "ReDoS in multipart 1.3.0 - `parse_options_header()`", "problemTypes": [{"descriptions": [{"cweId": "CWE-1333", "lang": "en", "description": "CWE-1333: Inefficient Regular Expression Complexity", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/defnull/multipart/security/advisories/GHSA-p2m9-wcp5-6qw3", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/defnull/multipart/security/advisories/GHSA-p2m9-wcp5-6qw3"}], "affected": [{"vendor": "defnull", "product": "multipart", "versions": [{"version": ">= 1.3.0, < 1.3.1", "status": "affected"}, {"version": "< 1.2.2", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-03-12T16:45:01.070Z"}, "descriptions": [{"lang": "en", "value": "multipart is a fast multipart/form-data parser for python. Prior to 1.2.2, 1.3.1 and 1.4.0-dev, the parse_options_header() function in multipart.py uses a regular expression with an ambiguous alternation, which can cause exponential backtracking (ReDoS) when parsing maliciously crafted HTTP or multipart segment headers. This can be abused for denial of service (DoS) attacks against web applications using this library to parse request headers or multipart/form-data streams. The issue is fixed in 1.2.2, 1.3.1 and 1.4.0-dev."}], "source": {"advisory": "GHSA-p2m9-wcp5-6qw3", "discovery": "UNKNOWN"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-03-13T16:29:21.955869Z", "id": "CVE-2026-28356", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"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": "2026-03-13T16:29:28.768Z"}}]}}

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{"cveTags": [], "descriptions": [{"lang": "en", "value": "multipart is a fast multipart/form-data parser for python. Prior to 1.2.2, 1.3.1 and 1.4.0-dev, the parse_options_header() function in multipart.py uses a regular expression with an ambiguous alternation, which can cause exponential backtracking (ReDoS) when parsing maliciously crafted HTTP or multipart segment headers. This can be abused for denial of service (DoS) attacks against web applications using this library to parse request headers or multipart/form-data streams. The issue is fixed in 1.2.2, 1.3.1 and 1.4.0-dev."}, {"lang": "es", "value": "multipart es un r\u00e1pido analizador de multipart/form-data para Python. Antes de 1.2.2, 1.3.1 y 1.4.0-dev, la funci\u00f3n parse_options_header() en multipart.py utiliza una expresi\u00f3n regular con una alternancia ambigua, lo que puede causar retroceso exponencial (ReDoS) al analizar encabezados HTTP o de segmento multipart maliciosamente elaborados. Esto puede ser abusado para ataques de denegaci\u00f3n de servicio (DoS) contra aplicaciones web que utilizan esta biblioteca para analizar encabezados de solicitud o flujos de multipart/form-data. El problema est\u00e1 solucionado en 1.2.2, 1.3.1 y 1.4.0-dev."}], "id": "CVE-2026-28356", "lastModified": "2026-04-16T14:47:16.733", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-03-12T17:16:50.080", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/defnull/multipart/security/advisories/GHSA-p2m9-wcp5-6qw3"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-1333"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{"bugzilla": {"description": "multipart: denial of service via maliciously crafted HTTP or multipart segment headers", "id": "2447059", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2447059"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-1333", "details": ["A flaw was found in multipart. The parse_options_header function in multipart.py uses a regular expression with an ambiguous alternation, causing an exponential backtracking (ReDoS) when parsing a specially crafted HTTP or multipart segment headers. A web application parsing request headers or multipart/form-data streams can block request handling threads for multiple seconds per request, eventually resulting in a denial of service."], "mitigation": {"lang": "en:us", "value": "Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible."}, "name": "CVE-2026-28356", "package_state": [{"cpe": "cpe:/a:redhat:lightspeed_core", "fix_state": "Affected", "package_name": "lightspeed-core/lightspeed-stack-rhel9", "product_name": "Lightspeed Core"}, {"cpe": "cpe:/a:redhat:lightspeed_core", "fix_state": "Affected", "package_name": "lightspeed-core/rag-tool-rhel9", "product_name": "Lightspeed Core"}, {"cpe": "cpe:/a:redhat:openshift_lightspeed", "fix_state": "Affected", "package_name": "openshift-lightspeed/lightspeed-ocp-rag-rhel9", "product_name": "OpenShift Lightspeed"}, {"cpe": "cpe:/a:redhat:openshift_lightspeed", "fix_state": "Affected", "package_name": "openshift-lightspeed/lightspeed-service-api-rhel9", "product_name": "OpenShift Lightspeed"}, {"cpe": "cpe:/a:redhat:ai_inference_server:3", "fix_state": "Affected", "package_name": "rhaiis-preview/vllm-cuda-rhel9", "product_name": "Red Hat AI Inference Server"}, {"cpe": "cpe:/a:redhat:ai_inference_server:3", "fix_state": "Affected", "package_name": "rhaiis/vllm-cpu-rhel9", "product_name": "Red Hat AI Inference Server"}, {"cpe": "cpe:/a:redhat:ai_inference_server:3", "fix_state": "Affected", "package_name": "rhaiis/vllm-cuda-rhel9", "product_name": "Red Hat AI Inference Server"}, {"cpe": "cpe:/a:redhat:ai_inference_server:3", "fix_state": "Affected", "package_name": "rhaiis/vllm-neuron-rhel9", "product_name": "Red Hat AI Inference Server"}, {"cpe": "cpe:/a:redhat:ai_inference_server:3", "fix_state": "Affected", "package_name": "rhaiis/vllm-rocm-rhel9", "product_name": "Red Hat AI Inference Server"}, {"cpe": "cpe:/a:redhat:ai_inference_server:3", "fix_state": "Affected", "package_name": "rhaiis/vllm-spyre-rhel9", "product_name": "Red Hat AI Inference Server"}, {"cpe": "cpe:/a:redhat:ai_inference_server:3", "fix_state": "Affected", "package_name": "rhaiis/vllm-tpu-rhel9", "product_name": "Red Hat AI Inference Server"}, {"cpe": "cpe:/a:redhat:ansible_automation_platform:2", "fix_state": "Not 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"Affected", "package_name": "rhelai3/bootc-azure-rocm-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Affected", "package_name": "rhelai3/bootc-cuda-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Affected", "package_name": "rhelai3/bootc-gcp-cuda-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Affected", "package_name": "rhelai3/bootc-rocm-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:enterprise_linux_ai:3", "fix_state": "Affected", "package_name": "rhelai3/disk-image-cuda-rhel9", "product_name": "Red Hat Enterprise Linux AI (RHEL AI) 3"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-caikit-nlp-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": 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OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-pipeline-runtime-pytorch-llmcompressor-cuda-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-pipeline-runtime-pytorch-rocm-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-pipeline-runtime-tensorflow-cuda-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-pipeline-runtime-tensorflow-rocm-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-trustyai-garak-lls-provider-dsp-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", 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"package_name": "rhoai/odh-workbench-jupyter-pytorch-rocm-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-workbench-jupyter-tensorflow-cuda-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-workbench-jupyter-tensorflow-rocm-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-workbench-jupyter-trustyai-cpu-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Affected", "package_name": "satellite/foreman-mcp-server-rhel9", "product_name": "Red Hat Satellite 6"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Affected", "package_name": "satellite/iop-advisor-engine-rhel9", "product_name": "Red Hat Satellite 6"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Affected", "package_name": "satellite/iop-host-inventory-rhel9", "product_name": "Red Hat Satellite 6"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Affected", "package_name": "satellite/iop-vmaas-rhel9", "product_name": "Red Hat Satellite 6"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Affected", "package_name": "satellite/iop-vulnerability-engine-rhel9", "product_name": "Red Hat Satellite 6"}], "public_date": "2026-03-12T16:45:01Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-28356\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-28356\nhttps://github.com/defnull/multipart/security/advisories/GHSA-p2m9-wcp5-6qw3"], "statement": "This issue is only exploitable in applications using the multipart.parse_form_data function directly or indirectly when parsing request headers or multipart/form-data streams. Also, the security impact of this flaw is limited to a denial of service, there is no corruption of memory or arbitrary code execution. Due to these reasons, this vulnerability has been rated with an important severity.", "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[1.3.0,1.3.1)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.2.2)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "multipart", "source": "cna", "vendor": "defnull"}, "product": "multipart", "vendor": "defnull"}], "analysis": {"en": {"generated_at": "2026-03-18T14:58:44.534853+00:00", "value": {"mitigation_remediation": ["Upgrade defnull/multipart to version 1.2.2, 1.3.1, or 1.4.0\u2011dev or later."], "summary": {"action": "Patch Immediately", "impact": "Denial of Service"}, "threat_synthesis": {"affected_systems": "All users of the defnull:multipart library whose installed version precedes the fixes are affected. Specifically, any release before 1.2.2, before 1.3.1, or before 1.4.0\u2011dev contains the flaw. Projects that employ versions 1.0.x through 1.3.0 or any 1.4.0\u2011dev snapshot prior to the release of the patched version must be updated.", "description_and_impact": "The vulnerability resides in defnull's multipart library. Its parse_options_header() function relies on a regular expression that contains an ambiguous alternation, leading to exponential backtracking when parsing maliciously crafted HTTP or multipart segment headers. This results in a ReDoS condition that can be leveraged to exhaust server resources and cause a denial of service. The weakness corresponds to CWE\u20111333.", "risk_and_exploitability": "The CVSS base score is 7.5, indicating moderate to high severity for denial of service. The EPSS score is below 1\u202f%, showing a low current probability of exploitation. The vulnerability is not listed in CISA's KEV catalog. Because the flaw is triggered by forged request headers, an attacker can execute the attack remotely via the application\u2019s HTTP interface, provided the application allows multipart form data. The impact is limited to application availability and does not affect confidentiality or integrity directly."}}}}, "created": "2026-03-13T09:51:03.899183+00:00", "updated": "2026-03-20T15:48:57.264951+00:00", "vendors": ["defnull", "defnull$PRODUCT$multipart"]}