A Study to Evaluate the Safety, Tolerability, Pharmacokinetics (PK) and Preliminary Clinical Activity of RO7673396 in Participants With Advanced Solid Tumors Harboring Rat Sarcoma Viral Oncogene Homolog (RAS) Mutation(s)

Inclusion Criteria: * Histologically documented, locally advanced, recurrent, or metastatic incurable solid tumors * Participants with measurable disease according to RECIST v1.1 assessed by the investigator * Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 * Life expectancy ≥12 weeks * Adequate hematologic and end-organ function * Confirmed presence of the RAS mutation(s) Exclusion Criteria: * Current participant or enrollment in another interventional clinical trial * Known hypersensitivity or medical contraindication to any component of RO7673396 formulation * Refractory nausea and vomiting, malabsorption, external biliary shunt, or significant small bowel resection that would preclude adequate study treatment absorption * Known and untreated, or active central nervous system (CNS) metastases * Participants with chronic diarrhea, short bowel syndrome or significant upper gastrointestinal (GI) surgery including gastric resection, a history of inflammatory bowel disease (IBD) * Treatment with chemotherapy, immunotherapy, biologic therapy, or an investigational agent as anti-cancer therapy within 4 weeks or five half-lives prior to initiation of study treatment * Participants who are on acid-reducing agents and unable to safely discontinue them as required in the study * Major surgical procedure within 28 days prior to initiation of study treatment, or incomplete recovery from surgery that would interfere with the determination of safety or efficacy of study treatment, or anticipation of need for a major surgical procedure during the study * A history of idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced pneumonitis, idiopathic pneumonitis, non-infectious ILD/pneumonitis, or current evidence of active pneumonitis or ILD on screening chest CT scan * Uncontrolled pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures * Known clinically significant liver disease