Vodafone admitted Tuesday it found security flaws in Huawei's telecommunications equipment in 2011 and 2012, a revelation that could further stain the reputation of the Chinese tech giant.
U.K.-based Vodafone, the world's second-largest mobile operator, said in a statement it had found security vulnerabilities in Huawei technology supplied to its Italian business dating back to 2011. The vulnerabilities, which were first reported Tuesday by Bloomberg, have since been resolved, both companies confirmed to CNBC.
"The issues were identified by independent security testing, initiated by Vodafone as part of our routine security measures, and fixed at the time by Huawei," Vodafone said in a statement.
Vodafone said there is no evidence that Huawei gained "unauthorized access" to its networks, adding "this was nothing more than a failure to remove a diagnostic function after development."
"Software vulnerabilities are an industry-wide challenge," a Huawei spokesperson told CNBC. "Like every ICT vendor we have a well established public notification and patching process, and when a vulnerability is identified we work closely with our partners to take the appropriate corrective action."
Huawei is the world's biggest telecommunications equipment maker and has been under intense scrutiny for its role in building out 5G networks around the world. 5G is a fifth-generation wireless network that promises faster speeds and lower latency, increasing download speeds for consumers and potentially transforming industries like the internet of things and self-driving cars.
U.S. officials are pressuring allies to block Huawei from providing 5G equipment, arguing it could provide a backdoor for Chinese spying. Huawei has repeatedly denied it would engage in any form of espionage or provide data to the Chinese government. Experts have been skeptical about Huawei's assurances that it isn't a security risk, pointing to Chinese laws that allegedly mean every domestic company is legally mandated to assist the country in intelligence gathering if Beijing requests it.
Last week, Britain's National Security Council reportedly agreed to let Huawei provide some equipment for the nation's 5G networks. A report last month from the U.K. government found Huawei equipment raises "significant" security risks but it did not link the security risks to Chinese state interference.
Vodafone already uses Huawei's equipment in many of its existing mobile networks. In March, Vodafone CEO Nick Read said a ban on Huawei could set back Europe's 5G rollout by two more years.