CVE-2026-5778

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{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,5.9.0]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "wolfSSL", "source": "cna", "vendor": "wolfSSL"}, "product": "wolfssl", "vendor": "wolfssl"}], "analysis": {"en": {"generated_at": "2026-04-10T00:24:13.677565+00:00", "value": {"mitigation_remediation": ["Upgrade wolfSSL to a version newer than 5.9.0.", "If upgrade cannot be performed immediately, disable the packet sniffer or the ChaCha decryption path.", "Monitor logs for crashes or segmentation faults that may indicate exploitation attempts."], "summary": {"action": "Patch", "impact": "Denial of Service via program crash"}, "threat_synthesis": {"affected_systems": "wolfSSL library versions 5.9.0 and earlier contain the vulnerable logic. Any deployment that activates the packet sniffer on traffic that includes TLS records, regardless of the host operating system or programming language, may be affected.", "description_and_impact": "An integer underflow in the packet sniffer\u2019s ChaCha decrypt path misinterprets a TLS record length, causing the AEAD routine to read a large, invalid buffer. This out\u2011of\u2011bounds read terminates the process, yielding a denial\u2011of\u2011service condition. The flaw is a classic integer underflow (CWE\u2011191) that does not disclose data or alter the encrypted content.", "risk_and_exploitability": "With a CVSS score of 2.1 the vulnerability is considered low severity. The exploit does not require authentication and can be triggered remotely by sending malformed TLS Application Data records. The attacker only gains a process crash, leading to denial of service. There is no evidence of active exploitation, as it is not listed in the CISA known exploited vulnerabilities catalog, and the EPSS score is unavailable."}}}}, "created": "2026-04-10T08:36:45.473026+00:00", "updated": "2026-04-10T09:27:42.246186+00:00", "vendors": ["wolfssl", "wolfssl$PRODUCT$wolfssl"]}