Malicious PDF — malware analysis report

Static analysis result for SHA-256 56178c3ec1f714fc…

MALICIOUS

PDF

12.0 KB
MD5: a033f56df97cd51398def20f4bb2a140 SHA-1: 0ae043b7e290a865be2678d09c9f3cddcb1512e0 SHA-256: 56178c3ec1f714fca7557c050aefe974af0b2fe1bafce4edcc3f080c1c50bfec
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link or Macro: User Execution: Malicious Link T1204.002 Malicious Link or Macro: User Execution: Malicious Macro

The PDF file contains embedded JavaScript, triggered by the CVE-2007-5659 vulnerability using the 'collab.collectEmailInfo' method. This JavaScript is heavily obfuscated and appears to be a stager, indicating it's designed to download and execute a second-stage payload. The presence of multiple deobfuscated JavaScript files suggests a complex execution chain.

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
f9393392f88aad0ccea34281b96f322370c12447012015834f8fcd5eabf72368
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5061 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
857454f5f1d2b51fb18fee98e21fb4205c6da2646a82c1c44172711f0c6a9b32
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12195 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
417f9c864634850ae7681876a4b43404dfdf3fee75202236812b11c906125e19
deobfuscated-js PDF JavaScript deobfuscation pass 79272 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).