CVE-2026-63384

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has an incorrect integer conversion in event_tagging.c when evtag_unmarshal_header uses evtag_decode_int to decode an attacker-controlled uint32 payload length and returns it as a signed int. Values above INT_MAX become negative or truncated, and evtag_unmarshal_string can use the converted value in allocation sizing, producing a wrapped large allocation request and denial of service. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.

CVSS

No CVSS.

References

Link	Resource
https://github.com/libevent/libevent/commit/109c16499282959d70f56ec3baf4c8b1e6646bda
https://github.com/libevent/libevent/commit/5e3c6ebe342b34c5a9bcf48e9a32ad6708b9c416
https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable
https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha
https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8
https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8

Configurations

No configuration.

History

26 Oct 2026, 10:10

Type	Values Removed	Values Added
Summary		(es) Libevent es una biblioteca de notificación de eventos. Antes de las versiones 2.1.13 y 2.2.2-alpha, libevent tiene una conversión de entero incorrecta en event_tagging.c cuando evtag_unmarshal_header usa evtag_decode_int para decodificar una longitud de carga útil uint32 controlada por el atacante y la devuelve como un entero con signo. Valores superiores a INT_MAX se vuelven negativos o truncados, y evtag_unmarshal_string puede usar el valor convertido en el dimensionamiento de la asignación, produciendo una solicitud de asignación grande envuelta y denegación de servicio. Este problema está corregido en las versiones 2.1.13 y 2.2.2-alpha.

Information

Published : 2026-08-20 18:16

Updated : 2026-10-26 10:10

NVD link : CVE-2026-63384

Mitre link : CVE-2026-63384

CVE.ORG link : CVE-2026-63384

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

{"id": "CVE-2026-63384", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-63384", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-20T19:50:07.634809Z"}}], "cvssMetricV40": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 8.7, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "libevent", "product": "libevent", "versions": [{"status": "affected", "version": ">= 2.2.0-alpha, < 2.2.2-alpha"}, {"status": "affected", "version": "< 2.1.13"}]}]}], "published": "2026-08-20T18:16:36.367", "references": [{"url": "https://github.com/libevent/libevent/commit/109c16499282959d70f56ec3baf4c8b1e6646bda", "source": "security-advisories@github.com"}, {"url": "https://github.com/libevent/libevent/commit/5e3c6ebe342b34c5a9bcf48e9a32ad6708b9c416", "source": "security-advisories@github.com"}, {"url": "https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable", "source": "security-advisories@github.com"}, {"url": "https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha", "source": "security-advisories@github.com"}, {"url": "https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8", "source": "security-advisories@github.com"}, {"url": "https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-190"}]}], "descriptions": [{"lang": "en", "value": "Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has an incorrect integer conversion in event_tagging.c when evtag_unmarshal_header uses evtag_decode_int to decode an attacker-controlled uint32 payload length and returns it as a signed int. Values above INT_MAX become negative or truncated, and evtag_unmarshal_string can use the converted value in allocation sizing, producing a wrapped large allocation request and denial of service. This issue is fixed in versions 2.1.13 and 2.2.2-alpha."}, {"lang": "es", "value": "Libevent es una biblioteca de notificaci\u00f3n de eventos. Antes de las versiones 2.1.13 y 2.2.2-alpha, libevent tiene una conversi\u00f3n de entero incorrecta en event_tagging.c cuando evtag_unmarshal_header usa evtag_decode_int para decodificar una longitud de carga \u00fatil uint32 controlada por el atacante y la devuelve como un entero con signo. Valores superiores a INT_MAX se vuelven negativos o truncados, y evtag_unmarshal_string puede usar el valor convertido en el dimensionamiento de la asignaci\u00f3n, produciendo una solicitud de asignaci\u00f3n grande envuelta y denegaci\u00f3n de servicio. Este problema est\u00e1 corregido en las versiones 2.1.13 y 2.2.2-alpha."}], "lastModified": "2026-10-26T10:10:00.140", "sourceIdentifier": "security-advisories@github.com"}