Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4809c2e849f4c05…

MALICIOUS

PDF

9.6 KB
MD5: 86b14a766f3986df7b28dc5bcb25ea50 SHA-1: 2ac95413fa901bd5b6afecf114c62a67aad73d50 SHA-256: e4809c2e849f4c05ebdb2c8bca22bdc032f4ccc85a12f044a867dfb75940529c
186 Risk Score

Malware Insights

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

The PDF sample contains heavily obfuscated JavaScript, identified by multiple heuristics including CVE-2007-5659 and ClamAV detection. The embedded JavaScript, particularly the deobfuscated.js artifact, is responsible for the malicious behavior. This script likely downloads and executes a second-stage payload, as indicated by the 'annotation_subject_callee_hex_stager' heuristic. The specific attack pattern involves exploiting PDF reader vulnerabilities to achieve arbitrary code execution.

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: 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
11b03694c4e705ab29873cc5e2c55342ee498b376ac2dc5f05ce17018ef44c38
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 264 bytes
annotation_subject_callee_hex_stage_000.js
ffaac900a8aae1d11e5fe6ece6a4f42d38d87087ae36ca1953e75c26e13cdbbf
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5208 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
bee65aa443f6b0f5be95abc0ac121b2f50a3dd493d0452419801717e863825de
deobfuscated-js PDF JavaScript deobfuscation pass 75422 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).