Malicious PDF — malware analysis report

Static analysis result for SHA-256 aaa8dde681e0b743…

MALICIOUS

PDF

9.6 KB
MD5: f1b6753e23d8ba04d409823123c2f631 SHA-1: 54d2842700cd3c0b6a3057bc3303088f6dcceb9e SHA-256: aaa8dde681e0b743575f5989a63d1e83be1e0dc22b22b411ff09dad8f2aca091
178 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is obfuscated and uses the unescape() function, indicating malicious intent. The critical heuristic CVE_2007_5659 specifically points to the exploitation of a known vulnerability (Collab.collectEmailInfo) via JavaScript. ClamAV also detected this as Pdf.Exploit.Agent-35905. The extracted JavaScript streams are large and complex, suggesting they are designed to download and execute a second-stage payload.

Heuristics 6

  • 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.Exploit.Agent-35905 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35905
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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.
  • 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
d8a6b4ad1abf04d0c4a4f89535cfb57f7312edef25c443f4e844c8ec9d0929dd
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 352 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
83391ab2fa33e42efc03191d1465575f702b9fb2e1be9295afa23a04d59ecdd2
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 12421 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
ef9be42eafe3c94d6b54cf17698c1d446179607406a66d88021ce7a4e0667b00
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 5171 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).