Fallos del tipo CWE-191

399 resultados

Subfluxo de inteiro (estouro negativo)

Ocorre quando uma operação aritmética subtrai um valor maior de um inteiro não assinado, causando wraparound: o resultado "volta" para um número muito grande em vez de ficar negativo. Um inteiro de 8 bits sem sinal (0-255), ao subtrair 1 de 0, vira 255. Isso quebra lógica de validação e pode ser explorado para contornar limites de segurança, alocar memória inadequada ou acessar áreas indevidas.

Ejemplo

Um sistema de download que valida se o tamanho solicitado cabe em buffer: se recebe tamanho=0 e subtrai um header de 10 bytes, a conta (0 - 10) em inteiro não assinado resulta em 4.294.967.286 bytes em uma arquitetura de 32 bits, enganando a validação e causando overflow no buffer.

Cómo mitigar

Sempre validar entrada antes de operações aritméticas; usar tipos assinados quando desejar representar negativos; implementar verificações de limites (p.ex., se A < B antes de calcular A - B); usar ferramentas estáticas ou sanitizers (AddressSanitizer, UBSan) para detectar wraparound em tempo de desenvolvimento.

CVE-2023-38427CRITICALAn issue was discovered in the Linux kernel before 6.3.8. fs/smb/server/smb2pdu.c in ksmbd has an integer underflow and out-of-bounds read iEPSS 1.2%CVE-2022-3165MEDIUMAn integer underflow issue was found in the QEMU VNC server while processing ClientCutText messages in the extended format. A malicious clieEPSS 1.2%CVE-2023-36796HIGHVisual Studio Remote Code Execution VulnerabilityEPSS 1.2%CVE-2023-36794HIGHVisual Studio Remote Code Execution VulnerabilityEPSS 1.2%CVE-2023-43628MEDIUMAn integer underflow vulnerability exists in the NTRIP Stream Parsing functionality of GPSd 3.25.1~dev. A specially crafted network packet cEPSS 1.2%CVE-2021-25121—Rating by BestWebSoft < 1.6 - Rating Denial of ServiceEPSS 1.2%CVE-2026-85436HIGHMOOS essential-moos through 10.0.1 pMOOSBridge Heap Corruption via Negative UDP LengthEPSS 1.2%CVE-2026-49181HIGHWindows DHCP Client Elevation of Privilege VulnerabilityEPSS 1.2%CVE-2022-0544—An integer underflow in the DDS loader of Blender leads to an out-of-bounds read, possibly allowing an attacker to read sensitive data usingEPSS 1.2%CVE-2023-31137HIGHMaraDNS Integer Underflow Vulnerability in DNS Packet DecompressionEPSS 1.1%CVE-2021-21811HIGHA memory corruption vulnerability exists in the XML-parsing CreateLabelOrAttrib functionality of AT&T Labs’ Xmill 0.7. A specially crafted XEPSS 1.1%CVE-2020-2031MEDIUMPAN-OS: Integer underflow in the management interfaceEPSS 1.1%CVE-2023-24911MEDIUMMicrosoft PostScript and PCL6 Class Printer Driver Information Disclosure VulnerabilityEPSS 1.1%CVE-2024-37981HIGHSecure Boot Security Feature Bypass VulnerabilityEPSS 1.1%CVE-2025-29912HIGHCryptoLib Has Heap Buffer Overflow Due to Unsigned Integer Underflow in Crypto_TC_ProcessSecurityEPSS 1.1%CVE-2015-8370HIGHMultiple integer underflows in Grub2 1.98 through 2.02 allow physically proximate attackers to bypass authentication, obtain sensitive inforEPSS 1.1%CVE-2025-29909HIGHCryptoLib's Crypto_TC_ApplySecurity() Has a Heap Buffer Overflow VulnerabilityEPSS 1.1%CVE-2024-47546MEDIUMGHSL-2024-243: GStreamer has an integer underflow in extract_cc_from_data leading to OOB-readEPSS 1.1%CVE-2024-47545MEDIUMGHSL-2024-242: GStreamer has an integer underflow in FOURCC_strf parsing leading to OOB-readEPSS 1.1%CVE-2022-1698CRITICALAllowing long password leads to denial of service in causefx/organizrEPSS 1.1%