Malicious PDF — malware analysis report

Static analysis result for SHA-256 e240a64d918eaebf…

MALICIOUS

PDF

12.0 KB
MD5: ac2fc81f7906455c55e6413216b69f35 SHA-1: 880b702c024950ac7d9f421231d8d453c080b4b3 SHA-256: e240a64d918eaebf5d2b3babbb2688caf0d34e2c8865ec59f4521a4f52cd7d8e
186 Risk Score

Malware Insights

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

The PDF document contains embedded JavaScript that is heavily obfuscated and uses a hex stager. Heuristics indicate the exploitation of CVE-2007-5659 via the Collab.collectEmailInfo method. The primary function of the embedded script appears to be downloading and executing a secondary payload, as suggested by the 'stager' designation and the presence of large, deobfuscated JavaScript artifacts.

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
3ee96a84987b12456468b740c95d07089c123893f57b07a7ad087ef377f718ff
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5063 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
f106278c6712bf51371d69138f79ee19b32b13f1e99b0729acc3625b2ca94c44
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12001 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
f0f43276e2dfe74ac47c5bfba529c6b4336d4acee45c355cb8a1898a4c139eac
deobfuscated-js PDF JavaScript deobfuscation pass 74569 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).