{"api_version":"1","generated_at":"2026-05-13T02:10:55+00:00","cve":"CVE-2026-42859","urls":{"html":"https://cve.report/CVE-2026-42859","api":"https://cve.report/api/cve/CVE-2026-42859.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-42859","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-42859"},"summary":{"title":"Neat VNC: Buffer overflow due to oversized RSA public keys","description":"Neat VNC is a VNC server library. Prior to 0.9.6, a pre-authentication stack buffer overflow exists in neatvnc in the RSA-AES security type handler. An unauthenticated remote attacker who can reach the VNC listening socket can send a crafted security type 5 (RSA-AES) or security type 129 (RSA-AES-256) handshake with an oversized client RSA public key, causing rsa_aes_send_challenge in src/auth/rsa-aes.c to overflow a 1024-byte on-stack buffer when encrypting the server challenge. This results in at least a denial of service via server crash. 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Prior to 0.9.6, a pre-authentication stack buffer overflow exists in neatvnc in the RSA-AES security type handler. An unauthenticated remote attacker who can reach the VNC listening socket can send a crafted security type 5 (RSA-AES) or security type 129 (RSA-AES-256) handshake with an oversized client RSA public key, causing rsa_aes_send_challenge in src/auth/rsa-aes.c to overflow a 1024-byte on-stack buffer when encrypting the server challenge. This results in at least a denial of service via server crash. This vulnerability is fixed in 0.9.6.","Type":"Description","Title":"Neat VNC: Buffer overflow due to oversized RSA public keys"}]}}}