Malicious PDF / .TXT — malware analysis report

Static analysis result for SHA-256 f948ddbdc838be08…

MALICIOUS

PDF / .TXT

12.9 KB
MD5: 6dd9f714d5ec961f80f7082401929532 SHA-1: a6608100b6754a58e9fba824ff5f9d62282e3468 SHA-256: f948ddbdc838be08a9aff69b94137a504ce1cb348fb8bcaee09fc21764c097ff
198 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: Malicious File T1059.001 Command and Scripting Interpreter: PowerShell

This PDF file exploits CVE-2007-5659 using a JavaScript stager embedded within annotation subjects. The deobfuscated JavaScript streams, legacy_pdfkit_stage_000.js and legacy_pdfkit_stage_001.js, are responsible for downloading and executing a second-stage payload. ClamAV also identified this file as Pdf.Exploit.Agent-36064.

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)
  • Annotation subject percent-decoding eval stager critical PDF_ANNOT_SUBJECT_MARKER_EVAL_STAGER
    OpenAction JavaScript forces annotation enumeration, reads an annotation /Subject payload with getAnnots(), rewrites marker bytes into percent escapes, decodes it with unescape(), and dispatches it through eval. This is a high-confidence exploit-kit staging pattern. It is intentionally not mapped to CVE-2009-1492 unless getAnnots() itself carries the crafted integer or long argument shape for that vulnerability.
  • ClamAV: Pdf.Exploit.Agent-36064 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36064
  • 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
a5c8f0f722df4dd9876a0087e1eee65bd3020c5995f94f6729f7e17f3f3677a0
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 331 bytes
legacy_pdfkit_stage_000.js
1ec08b0296986446e68d60929f63ec98d8f3f4c5f6335eb1b732c3bf6c05efc8
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2F2 11997 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
6bbf4de9517b1ed79c674eef810a175fc5f6244a69bcd3ff14850a89bfdc6df2
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2F2 5038 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).