Malicious PDF — malware analysis report

Static analysis result for SHA-256 651ec3b2f4ae4b6a…

MALICIOUS

PDF

45.4 KB
MD5: 80c6c870fb6afb827a5ed4e0862b2de2 SHA-1: 7f36934dbf795ce2cdd43ec727598ab8f725ab18 SHA-256: 651ec3b2f4ae4b6ad24369cd77fadb2112c121f2ef8bba3c1d462cf3b564b465
306 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 exploit, targeting Adobe Reader. The JavaScript is obfuscated and uses unescape() to decode a shellcode payload. This payload is designed to download and execute further malicious content, as indicated by the 'Pdf.Dropper.Agent' ClamAV detection and ML classifier score. The embedded URL 'http://www.bitstream.com' is a potential indicator for the second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 11

  • 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-7267553-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7267553-0
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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://www.bitstream.com
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0001_000.js
8f27727a66a8446c918fd543d4c250cbc24b4594754a9a8fd66fdba06ec7e0e4
pdf-javascript-stream PDF /JS object 1 at offset 0xA 2307 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
stream_002_off0000ac3e.js
d1dfd457a2fdd3cec4091f689f39b85b35666aa5599ef3a8d5f9a80d1e2ce105
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xAC3E 1042 bytes
font_00_sfnt_off00000e86.bin
550df6a15450a278a115a276e9ed55b732a6582de03ab8f47d66b27abcd8e7b9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE86 65932 bytes
font_01_type1_off0000b0e2.bin
c6bf78478c9c4dd5b3b86554d34c78f847f70af4118f9ff083c1fccf0e8e932b
pdf-font-stream PDF embedded font (type1) at offset 0xB0E2 97 bytes
font_02_type1_off0000b36b.bin
b749644b3e758e7335900ab2e7499eaa64b3a946849f1f8a0948287bdd96763d
pdf-font-stream PDF embedded font (type1) at offset 0xB36B 144 bytes