Malicious PDF — malware analysis report

Static analysis result for SHA-256 35a06606410376be…

MALICIOUS

PDF

13.0 KB
MD5: ef918802888a25bfbbe8f21648a0e0b6 SHA-1: a801d25b42caa33bbea4adcc823d932ed6996e29 SHA-256: 35a06606410376be40efd888c9a57fa7497521b9af7a038196f68623ff3753bd
188 Risk Score

Malware Insights

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

The PDF file contains obfuscated JavaScript, identified as a stager that exploits CVE-2007-5659. This exploit is designed to download and execute a second-stage payload. The presence of binary-XOR encoding and the use of String.fromCharCode indicate a deliberate attempt to obfuscate the malicious script. The ClamAV heuristic further confirms the malicious nature of the file.

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
  • Binary-XOR JavaScript stager high PDF_BINARY_XOR_JS_STAGER
    PDF JavaScript stores viewer-version payload branches as long binary digit strings, XORs each bit pair, converts 8-bit chunks with String.fromCharCode, and evals the recovered 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0049_000.js
f6d817c3fb9c481bb5af8e5f4d51da547bde7b3f6a9a1e4dae2466331a6ae686
pdf-javascript-stream PDF /JS object 49 at offset 0xA 76648 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 6 long base64-like blob(s).
binary_xor_stage_000.js
e3d22a61ca9a745d0033eb8b536fee211344b43ec2d2ade9f0edb73dc7cc300b
deobfuscated-js binary-XOR decoded JavaScript at offset 0x464 1270 bytes