Malicious PDF — malware analysis report

Static analysis result for SHA-256 948cfbd38832b72c…

MALICIOUS

PDF

13.3 KB
MD5: d9112243638d5bc46068d58ec80f65c8 SHA-1: 90cc0ba177850653ebc2146a37241c7395257e45 SHA-256: 948cfbd38832b72c92b0a64e3ec50713630ca9fc7721dafa8e60a6010deb94e1
186 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is obfuscated using binary-XOR encoding. This script exploits CVE-2007-5659 (Collab.collectEmailInfo) in Adobe Reader to execute a second-stage payload. The ClamAV detection name 'Pdf.Dropper.Agent-7283943-0' further confirms its malicious nature as a dropper. The primary attack vector is the exploitation of a known Adobe Reader vulnerability to download and execute further malicious content.

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.Dropper.Agent-7283943-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7283943-0
  • 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
9addff4dc38bc733a140f5e258e21af4c79874c85af1a7b1ee80d1c6b79553ca
pdf-javascript-stream PDF /JS object 49 at offset 0xA 78664 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
8f8961e04e6f2bb4f582325346455d636da6a95dc255e36e2912577243662386
deobfuscated-js binary-XOR decoded JavaScript at offset 0x464 1312 bytes