Malicious PDF — malware analysis report

Static analysis result for SHA-256 36a5e85fade6cd4e…

MALICIOUS

PDF

11.8 KB
MD5: d330513dbcbcc3694880222e17fd0cf8 SHA-1: cbd6508335b564bd592db48701c7455f49f8c469 SHA-256: 36a5e85fade6cd4e03ad410bcfb72700139e856ff0a4ecfdd530ebc0b327fade
186 Risk Score

Malware Insights

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

The PDF file contains multiple embedded JavaScript streams and triggers heuristics related to known PDF exploits, specifically CVE-2007-5659 (Collab.collectEmailInfo). The presence of large, deobfuscated JavaScript files suggests complex malicious scripting. The primary attack vector appears to be the exploitation of a PDF reader vulnerability to execute this script, which likely downloads and executes a second-stage payload.

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
74742ea0f8e4088ba55b0d458438cf24ee27e82add4bd3182bfabce86b4c38b1
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5011 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
d8a81503a0ba3841e459f8f5981ca0b10858aa3fa47d0308a5e34cab67348c77
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 11809 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
85f4f41e0c94b96da430eaabb3e914bd24e089d81471b55dbb5afef0fae03866
deobfuscated-js PDF JavaScript deobfuscation pass 76037 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).