Malicious PDF — malware analysis report

Static analysis result for SHA-256 92dd8c4b3ed68eab…

MALICIOUS

PDF

11.8 KB
MD5: af50bec579263067373bca700fbd09ed SHA-1: 47a4356abf530376d6120a422220763ecac2c8c9 SHA-256: 92dd8c4b3ed68eab8ade27a7e4df0e22f6cef1ba5f8d4e538cf938b8fbaef849
186 Risk Score

Malware Insights

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

The PDF document contains embedded JavaScript, triggered by the CVE-2007-5659 exploit targeting the Collab.collectEmailInfo function. This JavaScript acts as a stager, recovering and evaluating obfuscated code. The recovered code is extensive and appears to be responsible for downloading and executing a second-stage payload, as indicated by the large size of the deobfuscated JavaScript artifacts and the ClamAV detection signature 'Pdf.Exploit.Agent-36063'.

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
0cd5e8f6591324a03f2e7dbf959130f4dfbe64e26b58ed9160903d4b99dd146b
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5014 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
c8aa5e46a4bbf942fd9ed77815a3668b0b5c7ac952b02213ff7cff996f0d53b1
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12043 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
7e0bf7c67a4e236b67b28d47e3c6dff967c266e8d277dda033f11f3657e3de30
deobfuscated-js PDF JavaScript deobfuscation pass 78421 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).