seregonwar/uaf-2023-28205PoC CVE-2023-28205: Vulnerabilità Use-After-Free in Apple WebKit
Questa vulnerabilità interessa Apple WebKit e può essere sfruttata tramite contenuti web appositamente predisposti, consentendo potenzialmente l'esecuzione di codice arbitrario nel contesto del processo WebKit.
La build di WebKit analizzata in questo repository è basata su WebKit-613.1.17.1 (famiglia PlayStation / Safari 15.4).
La proof of concept attiva una condizione use-after-free (UAF)
ritardando intenzionalmente la registrazione di oggetti JavaScript come
Map e Date durante le operazioni di structured cloning.
Questa finestra temporale consente al Garbage Collector (GC) di JavaScriptCore di recuperare oggetti ancora logicamente in uso, causando la dereferenziazione di puntatori obsoleti durante la prosecuzione dell'esecuzione.
SerializedScriptValueCloneDeserializer::deserialize()La vulnerabilità risiede nella logica di deserializzazione dello structured clone, in particolare nel modo in cui gli oggetti JavaScript appena creati vengono tracciati durante la deserializzazione ricorsiva.
In SerializedScriptValue.cpp, il deserializzatore utilizza contenitori
WebKit standard come:
Vector<JSObject*, 32> outputObjectStack;
Vector<JSMap*, 4> mapStack;
Vector<JSSet*, 4> setStack;
Questi contenitori Vector non vengono scansionati dal Garbage Collector.
Se un ciclo di garbage collection viene attivato durante la deserializzazione
(ad esempio a causa di pressione sulla memoria o esecuzione JS rientrante), gli
oggetti referenziati solo da questi contenitori potrebbero essere raccolti
erroneamente.
Il deserializzatore, tuttavia, continua a utilizzare questi puntatori pendenti, determinando una condizione use-after-free.
La patch di sicurezza ufficiale di WebKit (commit c9880de) sostituisce questi
contenitori con MarkedVector, una struttura compatibile con il GC che registra
correttamente i suoi contenuti come GC root.
Nella build analizzata:
MarkedVector non è implementatoCloneDeserializer utilizza ancora VectorCiò conferma che la build è completamente vulnerabile a CVE-2023-28205.
Il seguente crash è stato riprodotto in modo affidabile dalla PoC ed è coerente con una dereferenziazione di puntatore obsoleto successiva al GC.
SIGSEGV (11)0x0000000000000068SceNKWebProcesslibSceNKWebKit.sprxL'indirizzo di fault 0x68 indica una dereferenziazione di un puntatore base
NULL con offset di campo oggetto, una firma classica dell'accesso a un
oggetto JavaScript liberato.
Lo stato dei registri conferma:
RAX = 0x0 (base oggetto NULL)Questo comportamento di crash è una manifestazione diretta della
UAF CloneDeserializer descritta sopra.
#
# A user thread receives a fatal signal
#
# signal: 11 (SIGSEGV)
# thread ID: 101395
# thread name: SceNKWebProcessMain
# proc ID: 88
# proc name: SceNKWebProcess
# reason: page fault (user read data, page not present)
# fault address: 0000000000000068
#
# registers:
# rax: 0000000000000000 rbx: 0000000000000000
# rcx: 000000020017e000 rdx: ffffffff00000000
# rsi: fffe000000000002 rdi: 0000000201d8c000
# rbp: 00000007eeff9f20 rsp: 00000007eeff9dc0
# r8 : 0000000200194c60 r9 : 00000002005ddc70
# r10: 0000000000000004 r11: 0000000000000000
# r12: 0000000200200000 r13: 0000000201d8c000
# r14: 0000000200880a00 r15: 0000000201d8c000
# rip: 0000000804d03bc1 eflags: 00010206
# BrF: 000000080424da9b BrT: 0000000804d03aa0
#
# backtrace:
copyin: SceNKWebProcessMain has nonsleeping lock
# 000000080424daa0
# 00000008052127b1
# 0000000805224b1b
# 0000000805224b1b
# 0000000805224b92
# 0000000805224b1b
# 0000000805208549
# 00000008037cd403
# 0000000803ed90a5
# 0000000804c48bd2
# 00000008045e2295
# 0000000804073b3b
# 000000080337f214
# 0000000802c62f61
# 0000000803e2b04b
# 0000000804645f82
# 000000080306ddc0
# 0000000803a06adb
# 0000000802e77528
# 0000000804281a70
# 0000000803bff887
# 0000000000405181
# 0000000000403d84
# 00000000004045ef
# 0000000000000000
#
# dynamic libraries:
# /goHvLUnT0D/common/lib/NKWebProcess.self
# text: 0000000000400000:0000000000408000 r-x
# data: 000000000040c000:0000000000410000 rw-
# fingerprint: 9f75275c0c9e6a8f512c46351676ba9c00000000
# /goHvLUnT0D/common/lib/libkernel_web.sprx
# text: 0000000800000000:0000000800050000 r-x
# data: 0000000800054000:000000080008c000 rw-
# fingerprint: 5cc7d026be64eb384dc8edd813cf5dff00000000
# /goHvLUnT0D/common/lib/libSceLibcInternal.sprx
# text: 000000080008c000:00000008001c0000 r-x
# data: 00000008001c8000:00000008001e4000 rw-
# fingerprint: 10c2fb20aecfba270ab36512cc6bcd3c00000000
# /goHvLUnT0D/common/lib/libSceSysmodule.sprx
# text: 00000008001e4000:00000008001f0000 r-x
# data: 00000008001f4000:0000000800200000 rw-
# fingerprint: d53329218364300cfc9ac1ce2f5f319000000000
# /goHvLUnT0D/common/lib/libScePosixForWebKit.sprx
# text: 0000000800200000:0000000800204000 r-x
# data: 0000000800208000:000000080020c000 rw-
# fingerprint: 2540b10c69fafebe19bf6c817f06a5dd00000000
# /goHvLUnT0D/common/lib/libcairo.sprx
# text: 000000080020c000:0000000800318000 r-x
# data: 0000000800320000:0000000800324000 rw-
# fingerprint: 66924f66c3b2bcfd5877f0b6b53b17c800000000
# /goHvLUnT0D/common/lib/libcurl.sprx
# text: 0000000800324000:00000008003d0000 r-x
# data: 00000008003d4000:00000008003d8000 rw-
# fingerprint: d07498e9ec79386fc781c8feeea9aa2800000000
# /goHvLUnT0D/common/lib/libfontconfig.sprx
# text: 00000008003d8000:0000000800450000 r-x
# data: 0000000800454000:0000000800458000 rw-
# fingerprint: f588f705527618061e0a9e633018197300000000
# /goHvLUnT0D/common/lib/libfreetype.sprx
# text: 0000000800458000:0000000800500000 r-x
# data: 0000000800508000:000000080050c000 rw-
# fingerprint: 55f0bf21e56f35c305acd791696e05b100000000
# /goHvLUnT0D/common/lib/libharfbuzz.sprx
# text: 000000080050c000:00000008005cc000 r-x
# data: 00000008005d0000:00000008005d4000 rw-
# fingerprint: 0e11f91a091308d571226554af07ce4000000000
# /goHvLUnT0D/common/lib/libicu.sprx
# text: 00000008005d4000:0000000802504000 r-x
# data: 0000000802524000:0000000802528000 rw-
# fingerprint: 1ef63fd860c70ff5f8744411e1ba581800000000
# /goHvLUnT0D/common/lib/libpng16.sprx
# text: 0000000802528000:000000080255c000 r-x
# data: 0000000802560000:0000000802564000 rw-
# fingerprint: 1bb1e4c3acb314d2dd52df2ca6a7a03e00000000
# /goHvLUnT0D/common/lib/libSceIpmi.sprx
# text: 0000000802564000:0000000802570000 r-x
# data: 0000000802574000:0000000802588000 rw-
# fingerprint: d5f95ff9044c26f90ff63c82fb0bbf5c00000000
# /goHvLUnT0D/common/lib/libSceSysCore.sprx
# text: 0000000802588000:0000000802590000 r-x
# data: 0000000802594000:0000000802598000 rw-
# fingerprint: d577567a554a7563ef2327c820bf0ee200000000
# /goHvLUnT0D/common/lib/libSceNet.sprx
# text: 0000000802598000:00000008025d0000 r-x
# data: 00000008025d4000:00000008026e8000 rw-
# fingerprint: 979f14da6d4c7aa75cdd4d4b2f3281c900000000
# /goHvLUnT0D/common/lib/libSceNetCtl.sprx
# text: 00000008026e8000:00000008026f0000 r-x
# data: 00000008026f4000:00000008026f8000 rw-
# fingerprint: 162fbdf7aa83706cc0992108ca3393ae00000000
# /goHvLUnT0D/common/lib/libSceRandom.sprx
# text: 00000008026f8000:00000008026fc000 r-x
# data: 0000000802700000:0000000802704000 rw-
# fingerprint: 976d3ebefe3870b97bfa1d8e82f1df2d00000000
# /goHvLUnT0D/common/lib/libSceLibreSsl3.sprx
# text: 0000000802704000:000000080288c000 r-x
# data: 00000008028ac000:00000008028b0000 rw-
# fingerprint: bd895ec678ab2becafd45e954fba828400000000
# /goHvLUnT0D/common/lib/libSceRegMgr.sprx
# text: 00000008028b0000:00000008028b4000 r-x
# data: 00000008028b8000:00000008028bc000 rw-
# fingerprint: 50fe32bc796e1dbda2337287e42091d100000000
# /goHvLUnT0D/common/lib/libSceSystemService.sprx
# text: 00000008028bc000:00000008028f8000 r-x
# data: 00000008028fc000:0000000802908000 rw-
# fingerprint: 6fead8bbcbbf7002bee44d4d2104c8d300000000
# /goHvLUnT0D/common/lib/libSceMbus.sprx
# text: 0000000802908000:0000000802914000 r-x
# data: 0000000802918000:000000080291c000 rw-
# fingerprint: eaf5e1ec79a60c0293ad42c039a9ff1a00000000
# /goHvLUnT0D/common/lib/libSceAvSetting.sprx
# text: 000000080291c000:0000000802928000 r-x
# data: 000000080292c000:0000000802930000 rw-
# fingerprint: 6a745bdbf97da42d23745852daa2afc700000000
# /goHvLUnT0D/common/lib/libSceVideoOut.sprx
# text: 0000000802930000:0000000802948000 r-x
# data: 000000080294c000:0000000802950000 rw-
# fingerprint: 504c9ecf78fdc9adf3fcd3721dc3975100000000
# /goHvLUnT0D/common/lib/libSceVideoCoreServerInterface.sprx
# text: 0000000802950000:0000000802960000 r-x
# data: 0000000802964000:000000080296c000 rw-
# fingerprint: 4613f400001d613dda147326d8ef133900000000
# /goHvLUnT0D/common/lib/libSceNKWebKitRequirements.sprx
# text: 000000080296c000:0000000802bdc000 r-x
# data: 0000000802be0000:0000000802be8000 rw-
# fingerprint: aa200eff9a5fd90b0c6f12853aa1cbd200000000
# /goHvLUnT0D/common/lib/libSceNKWebKit.sprx
# text: 0000000802be8000:00000008060b8000 r-x
# data: 00000008062c0000:00000008062f8000 rw-
# fingerprint: bc8a78e3ddb906f6d0de352329701c2600000000
# /goHvLUnT0D/common/lib/libSceGLSlimClientVSH.sprx
# text: 00000008062f8000:0000000806318000 r-x
# data: 000000080631c000:0000000806320000 rw-
# fingerprint: 1cea1ecf4ffd91dc02ca2b7bc92c3c0a00000000
<118>[Syscore App] App Crash : PID=0x58, reason=0xb
<118>[Syscore App] Syscore Event Queue Push : SCE_SYSCORE_EVENT_APP_CRASH
<118>[Syscore App] Syscore Event Queue Pop : SCE_SYSCORE_EVENT_APP_CRASH
<118>[SceLncService] AppCrash: pid={0x00000058} appId={0x60000201} appLocalPid={0x102012a5}
<118>[SceLncService] getCoredumpSequence() isDebuggable={0} isKeepProcess={1} isUserDebugRequest={0} isLimitKeepProcess={0} enableCrashReport={1}
<118>[SceLncService] CoredumpSequence = {DUMP_PROCESS}
<118>[SceLncService] getCoredumpMode() isSystem={0x00000001}, reason={0x0000000b}
<118>[SceLncService] notifyAppCrash() pid={0x00000058}, appId={0x60000201}, appLocalPid={0x102012a5}, coredump.path,name,mode={/user/data/sce_coredumps/NPXS20001_1767544376/,NPXS20001_1767544376.sorbisdmp,1}, enableCrashReport={1}, skipVshDump={0}
<118>[SceLncService] enableCrashReport={1}, crashReportMode={1}, isAllowed={0}
<118>[SceLncService] kick coredump is disabled.
<118>[Syscore App] Kill process: 0x58
<118>[VCS]closeSession() [APP->VCS] clientPid = 0x58.
<118>[Syscore App] EVFILT_PROC NOTE_EXIT received : pid=0x58
<118>[Syscore App] Kill process: 0x58 => 0
<118>[Syscore App] process delete event : pid=0x58
<118>[AppMgr Trace]: pid=0x58, deleted.
<118>[Syscore App] Syscore Event Queue Push : SCE_SYSCORE_EVENT_ON_PROCESS_UNLOADED
<118>[AppMgr] checkAppTerminated pid=0x2a is still alive in 0x60000201
<118>[Syscore App] Syscore Event Queue Pop : SCE_SYSCORE_EVENT_ON_PROCESS_UNLOADED
<118>[SceShellUI] W/PSM.UI : ** NOTICE: LoadSync : Parent_BrowserMain : FrameModalScene
<118>[SceShellUI] I/PSM.UI : OnFocusActiveSceneChanged [BrowserMain : MainScene] -> [Parent_BrowserMain : FrameModalScene]
<118>[SceShellUI] I/PSM.UI : Scene [Parent_BrowserMain : FrameModalScene] : Alive
<118>SetDeviceIndexBehavior: mode=SpecificUser, param=0x1a599820
<118>[Theme/I] : Apply [RED] : [Option:111111]: with preloaded user
<118>[SceShellCore] Libc Heap Status: free 38%, in-use 3794.3 KB, trend +18.1 KB/min, peak 4267.3 KB, when 19698 [sec]
<118>[SceShellCore] VM Stats: RSS 533.4, kernel 271.1, wire count 332.2, swap out 24.2, page table CPU 2526/6144 GPU 271/2048
La vulnerabilità fornisce una primitiva UAF stabile raggiungibile tramite
postMessage:
postMessageCiò consente una corruzione controllata della memoria delle strutture interne
di JavaScriptCore (ad es. StructureID, puntatori butterfly), rendendo questo
bug un forte candidato per uno sfruttamento affidabile con un adeguato
heap shaping.
CVE-2023-28205 è stata scoperta da Clément Lecigne (Google Threat Analysis Group) e Donncha Ó Cearbhaill (Amnesty International Security Lab).
Grazie a abc per l'ispirazione della proof-of-concept originale.
Basato sul repository poc uaf-2023-28205 di ntfargo