Mobile emergency alert systems in both countries were breached hours apart, sending fabricated warnings of radiation hazards and incoming missiles.
Hackers breached emergency alert mobile applications in both Ukraine and Russia late Sunday and early Monday, pushing out fabricated warnings of imminent nuclear strikes, chemical contamination and mass drone attacks to civilian phones.
The breaches came as a localized six-day humanitarian ceasefire in the southern Kherson region expired, PBS NewsHour reported. While official channels in both countries rushed to tell residents to ignore the notifications, it was not immediately clear whether the two cyberattacks were connected.
Fake nuclear and chemical warnings in Ukraine
In Ukraine, notifications began appearing on the Air Alert mobile app around 10:45 p.m. Kyiv time on Sunday, NBC News reported. The messages warned residents to stay indoors because of radiation hazards, chemical threats and street combat in and around Kyiv.
One message, sent in Russian, told users that a nuclear alert covered all of Ukraine and claimed that Russia’s Oreshnik intermediate-range ballistic missile was incoming, according to Al Jazeera. Other notifications arrived written in English with spelling and grammatical errors, or mixed Russian and Ukrainian phrases. In the western Lviv region, public sirens and loudspeaker systems briefly broadcast a radiation hazard signal.
Ukraine’s Air Force announced on Telegram that the app had been compromised by unauthorized third parties and urged calm, writing: “There is no radiation threat! Stay calm and follow our updates on our channel.”
The developers temporarily took the app offline before gradually bringing it back online. The Center for Strategic Communications in Ukraine blamed Russia for the breach, pointing to the Russian phrasing in the notifications. A Russian Telegram channel claimed that a hacking group named Hitcore carried out the intrusion, though that assertion could not be verified.
Yurii Ihnat, a spokesperson for Ukraine’s air force command, told the private 1+1 television channel that the attack had no effect on the country’s defense operations because the alert software operates entirely outside military command systems. The State Emergency Service later confirmed the national alert network was working normally.
Fabricated drone and missile alerts in Russia
Roughly four hours after the Ukrainian breach, Russia’s Ministry of Civil Defence, Emergencies and Disaster Relief experienced a similar cyberattack on its own mobile warning software. The alerts went out at about 2:45 a.m. Moscow time across 33 of the country’s 89 administrative regions.
The fake notifications told Russians that drones carrying nuclear warheads had been launched against all parts of the country. The messages told civilians to take shelter and urgently gather a three-week supply of food. Russian officials did not name suspects, describing the perpetrators only as malicious actors who exploited a digital vulnerability.
The Russian emergency ministry said the vulnerability was identified and addressed, adding that the mobile app is only a supplementary notification tool while broadcast sirens, text messages and media alerts remained secure. Kremlin spokesperson Dmitry Peskov stated that government agencies face persistent cyber threats and noted that “all government bodies must take steps to improve the cybersecurity of our digital resources.”
The end of the Oleshky humanitarian ceasefire
The digital disruptions arrived just as the longest pause in fighting since the 2022 invasion came to an end. The six-day localized truce, which began on Oct. 27, concluded at midnight at the start of Monday in the Russian-occupied city of Oleshky across the Dnipro River from Kherson.
The pause allowed humanitarian supplies to enter and enabled residents to leave for either Ukrainian-controlled or Russian-controlled areas. Ukrainian ombudsman Dmytro Lubinets said the oldest evacuee brought to Ukrainian territory was 94 years old, and rescue workers also brought out 104 pets. U.S. first lady Melania Trump helped broker the arrangement, with NBC News reporting that Pope Leo XIV was also involved.
Hours after the truce expired, Russian drone attacks struck Kherson, hospitalizing a 62-year-old woman and a 73-year-old man. Separate drone strikes injured 12 people in the Kharkiv region and five in Odesa, while Russian defense officials said they downed 212 Ukrainian drones overnight, including an aerial assault in the Samara region where an oil transport hub was targeted.
What happens next
Lubinets said Ukrainian officials are talking with Russian counterpart Yana Lantratova about future humanitarian initiatives. Negotiators are also trying to arrange further aid deliveries to the estimated 2,000 residents who remained in Oleshky.
Broader three-way negotiations involving Ukrainian, Russian and U.S. officials are expected later this month, with Ukrainian representatives hoping the Oleshky operation will serve as a model for further temporary truces.
