6e45ba2cfef34302f85bff6628f0c984bc991284ffd59faaa20ec244bfcd5f78

The file is the module exactly as the page had it. WebAssembly does nothing on its own: it runs only when a script instantiates it. Labels describe what the module contains and are leads, not verdicts.

At a glance

What it is
Not identified. Its build does not name it and it matches no library we know.
Names it came with
File name: crypto-signer. Its build and the addresses it came from say so; whoever builds a module chooses these, so they are hints.
How it was built
Written in Rust. wasm-bindgen connects it to the page's JavaScript.
What it can do
Its imports reach: cryptography. Judged from the names of its imports.
Where we saw it
On 1 public scan, 2026-10-16.
Findings
Nothing flagged by the checks below.
Size
44.9 KiB
First seen
2026-10-16
Last seen
2026-10-16
Public scans
1
Functions
103
Imports
29
Exports
12
Data segments
7

How it was built

Written in Rust. wasm-bindgen connects it to the page's JavaScript.

Language
RustImplied: wasm-bindgen is only used with Rust.
Connects to JavaScript
wasm-bindgenRust's bridge to JavaScript. It writes glue code on both sides, so the module can call page functions such as fetch or the DOM, and the page can call the module.
Rewritten after compiling
walrusA library for rewriting compiled modules. wasm-bindgen runs it on every build, so it comes with wasm-bindgen and says nothing more about the module.

Read from text inside the module (its build metadata and paths the compiler left) and from its import and export names. Whoever builds a module can change or remove these, so treat them as hints. They say how a module was made, not what it does.

What it is made of

3 Rust crates from crates.io, with the versions it was built with:

Build tools and versions it names:

  • Rust
  • rustc 1.85.1 (4eb161250 2025-03-15)
  • walrus 0.23.3
  • wasm-bindgen 0.2.100 (2405ec2b4)

Read from text the build left in the module: source paths, build metadata and .NET metadata. Whoever builds a module can change or remove it, so treat it as a hint.

Hashing and cipher code

Algorithms recognised from their published constants, tables and rotation amounts: SHA-256. Legitimate modules use them all the time, for hashing, captchas and encryption, so this is a lead, not a verdict.

  • cryptosigner_generateSignatureSHA-256 · a table it reads

Decompiled code

103 of 103 functions decompiled to C-like pseudocode; 29 more are imported from the page.

Decompiled code is a reconstruction from the file, so names and types are often guesses. Query values in URLs are masked here; the downloaded file is unchanged.

FunctionSizeBlocksComplexityNotes
No functions match.

File layout

WebAssembly binary format version 1, core module, 12 sections (2 custom).

SectionOffsetSizeItems
type0x8247 bytes35
import0xff1.1 KiB29
function0x547106 bytes103
table0x5b111 bytes2
memory0x5bc5 bytes1
global0x5c111 bytes1
export0x5cc269 bytes12
element0x6d955 bytes1
code0x71036.7 KiB103
data0x99d36.3 KiB7
custom: producers0xb2f4126 bytes
custom: target_features0xb37275 bytes
Memory
17 pages (1.1 MiB), no upper limit
Table 0
46 entries, up to 46 entries, funcref
Table 1
128 entries, no upper limit, externref
Globals
1
Element segments
1
Function names
none (names were stripped)
Target features
+mutable-globals +sign-ext +reference-types +multivalue

Data segments

Each bar is one segment of the module's data: as wide as its size, as tall as its entropy. Bars above the dashed line are encrypted or compressed. 7 segments, 6.2 KiB in all.

02468Segment 0: 357 bytes, 4.9 bits per byteSegment 1: 911 bytes, 5.18 bits per byteSegment 2: 51 bytes, 1.3 bits per byteSegment 3: 5,000 bytes, 6.55 bits per byteSegment 5: 49 bytes, 1.11 bits per byte
data segment encrypted or compressed 7.5 bits per byteHeight: bits per byte. Width: share of all the data.

Imports (29)

Can reach: crypto.

Imports from wbg are wasm-bindgen glue. Each __wbg_… import calls one JavaScript function in the page, and its name says which (__wbg_fetch_… calls fetch). The __wbindgen_… imports are wasm-bindgen's own helpers for strings, errors and memory.

  • wbg.__wbindgen_memory
  • wbg.__wbg_buffer_609cc3eee51ed158
  • wbg.__wbg_newwithbyteoffsetandlength_d97e637ebe145a9a
  • wbg.__wbg_randomFillSync_ac0988aba3254290
  • wbg.__wbg_subarray_aa9065fa9dc5df96
  • wbg.__wbg_getRandomValues_b8f5dbd5f3995a9e
  • wbg.__wbg_new_a12002a7f91c75be
  • wbg.__wbg_set_65595bdd868b3009
  • wbg.__wbg_crypto_574e78ad8b13b65f
  • wbg.__wbindgen_is_object
  • wbg.__wbg_process_dc0fbacc7c1c06f7
  • wbg.__wbg_versions_c01dfd4722a88165
  • wbg.__wbg_node_905d3e251edff8a2
  • wbg.__wbindgen_is_string
  • wbg.__wbg_require_60cc747a6bc5215a
  • wbg.__wbindgen_is_function
  • wbg.__wbindgen_string_new
  • wbg.__wbg_msCrypto_a61aeb35a24c1329
  • wbg.__wbg_newwithlength_a381634e90c276d4
  • wbg.__wbindgen_is_undefined
  • wbg.__wbg_newnoargs_105ed471475aaf50
  • wbg.__wbg_call_672a4d21634d4a24
  • wbg.__wbg_static_accessor_GLOBAL_88a902d13a557d07
  • wbg.__wbg_static_accessor_GLOBAL_THIS_56578be7e9f832b0
  • wbg.__wbg_static_accessor_WINDOW_5de37043a91a9c40
  • wbg.__wbg_static_accessor_SELF_37c5d418e4bf5819
  • wbg.__wbg_call_7cccdd69e0791ae2
  • wbg.__wbindgen_throw
  • wbg.__wbindgen_init_externref_table

Exports (12)

Scripts that carry or load it

  • handbook.fca.org.uk loads it; the script is minified or bundled.

From public scans. A script loads a module when it fetches or compiles it.

Text it passes to the page

Fixed text the module hands to the page's JavaScript when it calls an import, read from the module file. Imports that reach the network, run code or change the page come first; web addresses are shown as their host.

ImportText
wbg.__wbg_newnoargs_105ed471475aaf50return this
wbg.__wbindgen_string_newcrypto

In our sandbox

  • Produced 2 strings at run time, listed below.

Strings it produced at run time

Text that appeared while it ran and is not in the file: decoded, decrypted or built by its code. Web addresses are shown as their host.

  1. [...]begin <= end ( <= ) when slicing ``
  2. dh&6%n@)M

Checks we ran

  • Threat-feed matches: none
  • Names of mining software or pools: none
  • CryptoNight mining structure: not found
  • Hashing or cipher loops: none
  • Known hashing or cipher algorithms: SHA-256
  • Encrypted or compressed data: none
  • JavaScript stored inside: none
  • Other modules inside: none
  • Imports that read browser or page details: 1
  • Function names: removed (usual in release builds)

Static checks of the file: nothing in it was run for these. A finding is a lead, not a verdict.

Shares code with

Other modules that contain some of the same functions. They are ranked by functions few modules have, so a language's own runtime does not link every module built with it. Shared code often means a shared library or the same developer. It is a lead, not a verdict.

  • dedd9a7b…3a415f5.3 MiB · first seen 2026-10-08 · 16 functions in common (29% of this module's, 2% of that one's)
  • 4eb7b21e…cfee2d35.2 KiB · first seen 2026-10-05 · 9 functions in common (16% of this module's, 26% of that one's)
  • f28f1669…83f317226.1 KiB · first seen 2026-10-15 · 8 functions in common (14% of this module's, 3% of that one's)
  • 1edcf456…31803059.8 KiB · first seen 2026-10-04 · 7 functions in common (13% of this module's, 9% of that one's)
  • ffbb49b4…7b418e1.4 MiB · first seen 2026-10-27 · 7 functions in common (13% of this module's, under 1% of that one's)
  • c8f3ccc5…f01b152.7 MiB · first seen 2026-10-07 · 6 functions in common (11% of this module's, under 1% of that one's)
  • fe802a87…76a6d997.6 KiB · first seen 2026-10-20 · 6 functions in common (11% of this module's, 7% of that one's)
  • a384c2a2…8cf8d418.6 KiB · first seen 2026-10-18 · 3 functions in common (5% of this module's, 10% of that one's)

Seen on 1 public scan

PageTitleSeenHow it got there
handbook.fca.org.ukFCA Handbook2026-10-16Downloaded as a file