cbcvebase.
CVE-2019-5825
published 2019-11-25

CVE-2019-5825: Out of bounds write in JavaScript in Google Chrome prior to 73.0.3683.86 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML…

PriorityP181medium6.5CVSS 3.1
AVNACLPRNUIRSUCNINAH
KEVITWEXPLOIT
CISA Known Exploited Vulnerabilitydue 2022-06-22
Exploited in the wild
EPSS
55.93%
99.0th percentile
Out of bounds write in JavaScript in Google Chrome prior to 73.0.3683.86 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.

Affected

7 ranges
VendorProductVersion rangeFixed in
chromiumchromium>= 0 < 75.0.3770.80-175.0.3770.80-1
chromiumchromium>= 0 < 75.0.3770.80-175.0.3770.80-1
chromiumchromium>= 0 < 75.0.3770.80-175.0.3770.80-1
chromiumchromium>= 0 < 75.0.3770.80-175.0.3770.80-1
debianchromium< chromium 75.0.3770.80-1 (bookworm)chromium 75.0.3770.80-1 (bookworm)
googlechrome< 73.0.3683.8673.0.3683.86
googlechrome>= unspecified < 73.0.3683.8673.0.3683.86

Detection & IOCsextracted from sources · hover to see the quote

urlhttps://github.com/exodusintel/Chromium-941743↗
urlhttps://blog.exodusintel.com/2019/09/09/patch-gapping-chrome/↗
urlhttps://lordofpwn.kr/cve-2019-5825-v8-exploit/↗
command--no-sandbox↗
bytes↗
0x0, 0x61, 0x73, 0x6d, 0x1, 0x0, 0x0, 0x0, 0x1, 0x8, 0x2, 0x60, 0x1, 0x7f, 0x0, 0x60, 0x0, 0x0, 0x2, 0x19, 0x1, 0x7, 0x69, 0x6d, 0x70, 0x6f, 0x72, 0x74, 0x73, 0xd, 0x69, 0x6d, 0x70, 0x6f, 0x72, 0x74, 0x65, 0x64, 0x5f, 0x66, 0x75, 0x6e, 0x63, 0x0, 0x0, 0x3, 0x2, 0x1, 0x1, 0x7, 0x11, 0x1, 0xd, 0x65, 0x78, 0x70, 0x6f, 0x72, 0x74, 0x65, 0x64, 0x5f, 0x66, 0x75, 0x6e, 0x63, 0x0, 0x1, 0xa, 0x8, 0x1, 0x6, 0x0, 0x41, 0x2a, 0x10, 0x0, 0xb
  • →The exploit targets Chrome 73.0.3683.86 (64-bit) specifically; alert on User-Agent strings advertising this exact version being served exploit content. ↗
  • →Exploit delivery uses HTTP response headers 'Cache-Control: no-cache, no-store, must-revalidate', 'Pragma: no-cache', 'Expires: 0' with Content-Type text/html — look for this combination on pages serving JavaScript exploits. ↗
  • →The exploit uses WebAssembly to allocate an RWX memory region and writes shellcode into it; detect WebAssembly instantiation (WebAssembly.Instance/WebAssembly.Module) combined with typed array (BigUint64Array) manipulation in the same script context. ↗
  • →The exploit corrupts the length of a packed float array via Array.map callback to achieve out-of-bounds read/write; look for Array.map callbacks that allocate new typed arrays (BigUint64Array) and float arrays on index 0. ↗
  • →The exploit uses a known WebAssembly bytecode stub (magic bytes 0x00 0x61 0x73 0x6d) with a specific module structure; the exact byte sequence in bc[] can be used as a network or memory signature. ↗
  • →The Metasploit module exposes a /print endpoint for debug output; a URI path matching /print$ on a browser exploit server may indicate active exploitation or testing. ↗
  • →The exploit triggers page reload on failure via location.reload(); repeated rapid page reloads from a Chrome 73 UA to the same exploit URI may indicate exploitation retries. ↗
  • →The exploit reads the RWX page address at a fixed offset from the WasmInstance object (instance + 0xf8); this specific offset is version-fingerprinted to Chrome/73.0.3683.86 and can be used to distinguish targeted exploitation from generic WebAssembly use. ↗
  • ·The exploit only works when Chrome is launched with --no-sandbox; exploitation against default sandboxed Chrome installations will fail at payload execution stage. ↗
  • ·The exploit is architecture-specific (x86_64 only) and platform-limited to Windows and macOS; Linux and 32-bit targets are not supported by this module. ↗
  • ·The RWX memory offset used to locate the WebAssembly code page is hardcoded for Chrome 73.0.3683.86; different Chrome versions require different offsets and the exploit will not work against patched or other versions. ↗

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:N/A:P
osv6.5MEDIUM
vulncheck6.5MEDIUM
cisa6.5MEDIUM
vendor_debian6.5MEDIUM
vendor_redhat6.5MEDIUM
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