Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd874db8883855f7…

MALICIOUS

PDF

13.2 KB
MD5: ffc78576bdf824d951a30a6089eb3269 SHA-1: bb0e1299a270a96be79329c814bd3a22ab6ee3bf SHA-256: dd874db8883855f7edde9eedec637d7253c3a99e775dfa0e7afad44f75cbfd1a
186 Risk Score

Malware Insights

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

The PDF file contains obfuscated JavaScript that utilizes the CVE-2007-5659 vulnerability (Collab.collectEmailInfo) to execute a second-stage payload. The JavaScript is further obfuscated using binary-XOR encoding, indicating a deliberate attempt to evade detection. The primary goal appears to be the exploitation of Adobe Reader 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: 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
1bfc00b473a8c48d317edfc6adca2be11a4cfc9316c1c8f42199e556657070a1
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