Muongorori wezvekuchengetedza kweGoogle, Tavis Ormandy, aona kusazvibata kutsva (CVE-2023-23583) muIntel processors, codenamed Reptar, iyo inonyanya kutyisidzira kumaseti emafu anomhanyisa michina yevashandisi vakasiyana. Kusagadzikana kunogona kukonzera kuti sisitimu irembeke kana kuparara kana ichiita mamwe maoparesheni mumasisitimu evaenzi asina kurongeka. Chishandiso chinogadzira mamiriro ekushandiswa chakaburitswa nekuda kwekuyedza.
Nechifungidziro, kusazvibata kunogona kushandiswa kuwedzera kodzero kubva paring 3 kuenda ku0 (CPL0) uye kutiza nharaunda dziri kwadzo, asi mamiriro ezvinhu aya haasati asimbiswa mukuita nekuda kwekuomerwa kwekugadzirisa padanho rekuvakira. Kuyedzwa kwemukati kuIntel kwakaratidzawo mukana wekushandiswa kwekusagadzikana kweiyo rombo rekuwedzera mune mamwe mamiriro.
Sekureva kwemuongorori, kusazvibata kunobata Ice Lake, Rocket Lake, Tiger Lake, Raptor Lake, Alder Lake, uye Sapphire Rapids mhuri dzeIntel processors. Chirevo cheIntel chinoti nyaya iyi inobata chizvarwa chechigumi (Ice Lake) Intel Core processors uye yechitatu-chizvarwa Xeon Scalable processors, pamwe neXeon E/D/W processors (Ice Lake, Skylake, Haswell, Broadwell, Skylake, Sapphire Rapids, Emerald Rapids, Cascade Lake, Rombe Lake, Cascade Lake, Cascade Lake, Cooper Lake, Cascade Lake, Coscade Lake), (Apollo Lake, Jasper Lake, Arizona Beach, Alder Lake, Parker Ridge, Snow Ridge, Elkhart Lake, uye Denverton). Kusagadzikana kwakagadziriswa nezuro microcode update 20231114.
Kusagadzikana kunokonzerwa neimwe microarchitectural mamiriro apo kuitwa kwe "REP MOVSB" rairo yakavharwa neasina "REX" prefix, zvichitungamira kune isina kutsanangurwa maitiro. Nyaya yakawanikwa panguva yekuyedzwa kweakarebesa prefixes, iyo nedzidziso inofanirwa kufuratirwa asi mukuita yakatungamira kune zvinoshamisa mhedzisiro, sekuregeredza kusvetuka kusingaite uye kukanganisa pointer kuchengetedza mu xsave uye yekufona mirairo. Imwezve ongororo yakaratidza kuti kuwedzera chivakashure che "REP MOVSB" kuraira kunoshatisa zviri muROB (ReOrder Buffer), iyo inoshandiswa pakuraira kuraira.
Iko kukanganisa kunofungidzirwa kuve kwakakonzerwa nekuverengera kusiri kweiyo MOVSB saizi yekuraira, izvo zvinotungamira mukukanganisika mukutaura kwemirairo yakanyorwa kuROB buffer mushure meMOVSB ine prefix yakawandisa, uye kusarongeka kweinongedzo yekuraira. Iyi desynchronization inogona kugumira pakukanganisa kuverenga kwepakati nekudzoreredza kunotevera kwenzvimbo inowirirana. Nekudaro, kana tsaona ikakonzereswa panguva imwe chete pane akawanda cores kana SMT tambo, inogona kukonzera huwori hwakakwana hwekuita huwori hunokonzera kuparara.
Source: opennet.ru
