Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6d184fd7821928c…

MALICIOUS

PDF

12.0 KB
MD5: a3a9b7826b25852d41810f9f5795e834 SHA-1: b1f8d9b046f1008002ccb215b69451adab745a49 SHA-256: b6d184fd7821928c675ee6407e2f067e82c712012370972ffca3cd51c28dd4b2
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF file contains embedded JavaScript that is obfuscated and designed to be executed. Heuristics indicate the use of CVE-2007-5659, specifically targeting the `Collab.collectEmailInfo` function within Adobe Reader. The embedded JavaScript likely serves as a stager to download and execute a second-stage payload. The ClamAV detection of 'Pdf.Exploit.Agent-36063' further confirms the malicious nature of the file.

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
c22c5407d8b01036ef3773edabf3db8487d9b56dec2a080aefc40c21da964074
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5101 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
cfcd35d2fd00b23ce517563087bed9786a88d679ca876c2631d4f0806afce40b
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12127 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
4653f5f27f15c1fbc47aada95f3b0a5ee8cc3af5a56c5a4a7af7d3700b0b5062
deobfuscated-js PDF JavaScript deobfuscation pass 71549 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).