Malicious PDF — malware analysis report

Static analysis result for SHA-256 a235ddf2636b1381…

MALICIOUS

PDF

37.0 KB
MD5: 646019a10a987db94b25ee843c095013 SHA-1: 74bdd003c8afe2526b5ffd6b7734853bf685bc80 SHA-256: a235ddf2636b1381a7d206077aebe3b912cccafd95269b22eb3adc2eba349f9c
226 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution: Malicious Attachment T1059.001 Command and Scripting Interpreter: JavaScript T1059.003 Command and Scripting Interpreter: Windows Command Shell

The PDF file contains embedded JavaScript and U3D content, indicating an attempt to exploit vulnerabilities. Specifically, the 'CVE_2007_5659' heuristic firing points to the use of 'collab.collectEmailInfo' to execute a JavaScript stager. This stager is heavily obfuscated but ultimately aims to download and execute a second-stage payload, as suggested by the presence of multiple deobfuscated JavaScript files and a U3D stream.

Heuristics 8

  • 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)
  • U3D/3D content in PDF — Adobe Reader 3D parser CVE-family indicator high CVE related PDF_U3D_CVE_RELATED
    PDF contains U3D (Universal 3D) or 3D annotation content — CVE-2011-2462 and CVE-2009-3953 are critical vulnerabilities in Adobe Reader's U3D processing that allow arbitrary code execution. U3D content in PDFs is extremely rare in normal documents.
  • ClamAV: Heuristics.PDF.ObfuscatedNameObject critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Heuristics.PDF.ObfuscatedNameObject
  • 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
11b03694c4e705ab29873cc5e2c55342ee498b376ac2dc5f05ce17018ef44c38
pdf-javascript-stream PDF /JS object 7 at offset 0x1A4 264 bytes
annotation_subject_callee_hex_stage_000.js
492d2cc04582428cb884e93b8517fa932ceea29967e853425bd1535cf17a61a0
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x151 5408 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
cfa9eb2b5632a359d38317f57ddeae538201b4d0b8c9a34361583d3266e3b994
deobfuscated-js PDF JavaScript deobfuscation pass 270864 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
u3d_00_off000027af.bin
cffa1d7a24d7b9b42a43d7048cdc78d60069fa1b4ff10ec2aa0d89c3ba9ba702
pdf-3d-stream PDF U3D 3D stream at offset 0x27AF 27384 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.99, consistent with packed or encrypted content.