Malicious PDF — malware analysis report

Static analysis result for SHA-256 989a595d9be6802b…

MALICIOUS

PDF

12.0 KB
MD5: ed320d880e696453a9363a0c7679f52b SHA-1: 0c70fcf888a5d4b57efe6ca7e792cce4fd78e8ff SHA-256: 989a595d9be6802bdaa2b0bac41e32f74e7640f3ab3e8f62bf60d03b0bf8e100
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF document contains a critical heuristic firing for CVE-2007-5659, specifically utilizing the Collab.collectEmailInfo method to launch a JavaScript stager. This stager is heavily obfuscated but ultimately decodes and executes a payload. The presence of multiple deobfuscated JavaScript files indicates a multi-stage attack designed to download and run further malicious code. The primary attack vector is the exploitation of a known PDF vulnerability.

Heuristics 7

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • 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.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)
  • 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.

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
a12ae2c7250015334fa0de061487d99fbad6667c40d7679614d3d5780e3686ae
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5076 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
f707d640a4f407b6488a5d9fcf00ba7eb3d6aa13af5688b9d2ae2880f193eef8
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12236 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
159e6e69233eca003e8c8f5e7c2935d741be2cffbba478a69b058e86e047c937
deobfuscated-js PDF JavaScript deobfuscation pass 73623 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).