Malicious PDF — malware analysis report

Static analysis result for SHA-256 66f9391d65bef63b…

MALICIOUS

PDF

45.9 KB
MD5: 0700cb1e5f00e142d8210a7a0f250b6a SHA-1: 72a6a36bb436ee52b4f00753869bc8b47d880cbb SHA-256: 66f9391d65bef63bfd5e927a02dbbb59876caa41d4218a11d9567630f61dc5b5
346 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains embedded JavaScript that leverages the CVE-2010-2883 vulnerability in Adobe Reader. The JavaScript, after being deobfuscated, contains shellcode that is likely intended to download and execute a secondary payload. The presence of exploit cluster and critical heuristic firings strongly indicates malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 12

  • Adobe Reader CoolType SING font exploit — CVE-2010-2883 critical CVE likely CVE_2010_2883
    PDF embeds a TrueType/OpenType font with an actual SING table and pairs it with JavaScript heap-spray shellcode. This matches the public Adobe Reader CoolType SING exploit shape for CVE-2010-2883.
  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • ClamAV: Pdf.Dropper.Agent-7268298-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7268298-0
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • Generic recovered JavaScript exploit stage high PDF_GENERIC_STAGE_RECOVERY
    Bounded static stage recovery exposed hidden JavaScript through generic transforms such as null-byte collapse, percent decoding, marker replacement, arithmetic character codes, fromCharCode, numeric arrays, numeric-array minus-key decoders, alphabet-index arrays, /Producer half-difference metadata arrays, hex literals, marker-stripped Base64 literals, custom 6-bit XOR table decoders, or repeated-marker hex carriers. This rule is emitted only when the recovered stage contains exploit-like Acrobat JavaScript or shellcode markers.
  • Embedded script payload in PDF stream medium PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/3.0/
    • http://www.xfa.org/schema/xfa-template/3.0/
    • http://www.xfa.org/schema/xfa-data/1.0/

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
b92e144497d5691b0197eebaf25c33852e4267ed09a216c3dd55a60e96e534d9
pdf-javascript-stream PDF /JS object 6 at offset 0x348 2790 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
stream_002_off0000ae1e.js
d1dfd457a2fdd3cec4091f689f39b85b35666aa5599ef3a8d5f9a80d1e2ce105
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xAE1E 1042 bytes
generic_stage_recovery_000.js
7f90deea9c518a24059ee32623b9c0f33539cb39b5feb2b219ca10640b73e562
deobfuscated-js generic stage recovery split-literal-normalize from JavaScript object 6 at offset 0x348 2740 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
generic_stage_recovery_001.js
5294fc043dee769cf814de2432db727893dedbaf7b7218c99ba22fc0be462db1
deobfuscated-js generic stage recovery split-literal-normalize from decompressed stream at 0x0 at offset 0x0 46901 bytes
generic_stage_recovery_002.js
baa8a2bf24c6798687b775bd0307d98e0acca9c11bd05e044995c71c9f6da949
deobfuscated-js generic stage recovery split-literal-normalize -> percent-decode from decompressed stream at 0x0 at offset 0x0 46895 bytes
font_00_type1_off0000b2c2.bin
c6bf78478c9c4dd5b3b86554d34c78f847f70af4118f9ff083c1fccf0e8e932b
pdf-font-stream PDF embedded font (type1) at offset 0xB2C2 97 bytes
font_01_type1_off0000b54b.bin
b749644b3e758e7335900ab2e7499eaa64b3a946849f1f8a0948287bdd96763d
pdf-font-stream PDF embedded font (type1) at offset 0xB54B 144 bytes