PurposeThe purpose of this paper was identification and empirical assessment of the differentiation of consumers' attitudes in Ukraine and Poland to Russian brands and other brands offered on the Russian market after Russia’s aggression against Ukraine on February 24, 2022.Design/methodology/approachThe main research methods include a systematic literature review and the authors' own surveys conducted in November 2022. The research sample comprised 950 consumers – 67% of them were Poles, 30% – Ukrainians and 3% from other countries.FindingsA respondents' country (Poland and Ukraine) does not impact attitudes to brands offered on the Russian market after Russia's invasion of Ukraine on February 24, 2022. Moreover, it does not affect and differentiate emotional engagement in the conflict and assistance to war victims. Cluster analysis resulted in identifying two groups on the basis of consumers' declared emotional reactions to the war. The first group was smaller (N = 353, 37.2%), referred to as “indifferent consumers”, and was characterized by a greater inclination to purchase brands offered in Russia. The other cluster, referred to as “sensitive consumers” (N = 597, 62.8%), comprises those engaged in offering assistance to war victims, showing strong emotions in connection with the aggression and military activities and characterized by a clearly negative attitude to Russian and other offered brands and an inclination to boycott these brands.Research limitations/implicationsA short time horizon, the study confined to two countries, difficulties in reaching Ukrainian respondents due to power failures in Ukraine in the period of conducting the survey (November 2022), a non-representative research sample – overrepresentation of people aged 18–25 years.Practical implicationsThe research study contributes to the knowledge about consumer brand attitudes and preferences under unique social, economic and market conditions. These conditions were created by Russia's invasion of Ukraine in 2022, as well as the international and global character of the war in Ukraine. The significant implications of the study refer to brand communication policies and companies' CSR-related declarations. A number of consumers' errors were recorded, resulting from wrong brand retrieval, which were rectified at a later stage as a result of international restrictions imposed on Russia, harsh media criticism and social international embargoes imposed on brands offered in Russia. The marketing communication of contemporary global brands should give consideration to the informative function of CSR activities, and the communication process should be continuous. Critical attitudes and an inclination to boycott brands point to the possible consequences faced by inconsistent and ethically doubtful brand policies. This implication is clearly confirmed by the results of the study.Social implicationsThe authors also wish to highlight the implications for practice and society. As mentioned earlier, Polish consumers involved in providing aid to victims of the war also expressed their opposition to the war by boycotting Russian products and international brands remaining in Russia. Popularization of the research results obtained by the authors can be a form of sensitizing the public to the need for long-term relief, awakening global awareness of the essence and importance of sanctions imposed on Russia, as well as the possibility of expressing opposition through individual purchasing decisions and boycotting brands still present in Russia.Originality/valueThe study allowed for identifying consumers' differentiated brand attitudes in two countries: a country inflicted by war (Ukraine) and a front-line country, strongly supporting Ukraine (Poland). The research contributes to consumer behavior theories and studies of consumer attitudes and preferences from the perspective of international corporations' CSR activities under the unique conditions of war. Also, it contributes to the knowledge of the mechanism of forming attitudes to Russian and international brands offered in Russia among CEE consumers.