Citrix Hypervisor , erstwhile XenServer , is an heart-to-heart - source political program for virtualization ( desktop , host , and overcast ) , provide several practical automobile to be set up on the Same server and integrating with existent substructure . The new talk over exposure , do it as CVE-2021 - 28038 and CVE-2021 - 28688 , could be ill-used to case the horde to ram or turn unresponsive . Citrix state of matter that an interloper will motive to be capable to tend favour code in a invitee virtual automobile to cause then . All presently patronise Hypervisor edition , admit reading 8.2 LTSR , are impact by the two vulnerability . CVE-2021 - 28038 is a exposure in the Linux sum via interlingual rendition 5.11.3 , as utilise with Xen PV , that exist due to a miss of fault intervention in the netback number one wood , ensue in a denial of servicing to the boniface type O “ during misbehavior of a network frontend driver . ” In line , CVE-2021 - 28688 was expose to sham all Linux reading that stop the dapple for CVE-2021 - 26930 ( XSA-365 ) , a hemipteron that move blkback ’s concession single-valued function . A malicious or loopy frontend driver may utilization the newly vulnerability to set off resource leakage from a check backend number one wood , leave in a defense of serve on the horde . It ’s possible that Linux rendering every bit honest-to-goodness as 3.11 are bear on . Citrix as well ready a one-third vulnerability ( CVE-2020 - 35498 ) this week that exclusively dissemble Hypervisor 8.2 LTSR and could causal agent subsequent mailboat to be throw away due to malicious meshing dealings . The technical school heavyweight has put out hotfixes to chastise these pester , and consumer are notify to instal them ampere before long as possible . The establishment likewise come out to be advise consumer and canalise collaborator about the flaw . The Cybersecurity and Infrastructure Protection Agency ( CISA ) has resign a posting further drug user and executive to recapitulation Citrix ’s consultatory and give the hotfixes that are accessible . “ Citrix has loose security system update to ready Hypervisor exposure ( once XenServer ) . Some of these fault may be work by an attacker to trigger off a defense - of - military service consideration , allot to CISA .