Malicious PDF — malware analysis report

Static analysis result for SHA-256 44fcb61a5a1c3dbb…

MALICIOUS

PDF

6.7 KB
MD5: 68b7e67f6027867918948bfd265a240e SHA-1: 587df6c2c9281b4e8cd6e3820383e75c744ebc38 SHA-256: 44fcb61a5a1c3dbb7326736d64fe4287eb1690423f31b02ade312a5528740978
132 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages CVE-2014-0496 by using app.addToolButton/removeToolButton. This JavaScript is further obfuscated and appears to be a downloader for a second-stage payload, as indicated by the 'base26_stage_000.js' artifact. The primary intent is to execute arbitrary code by exploiting a known PDF vulnerability.

Heuristics 7

  • app.addToolButton/removeToolButton — CVE-2014-0496 critical CVE exact CVE_2014_0496
    PDF JavaScript combines app.addToolButton() and app.removeToolButton() with heap-spray shellcode markers — the public Adobe Reader/Acrobat ToolButton use-after-free exploit shape for CVE-2014-0496. (identified after JavaScript deobfuscation)
  • Suspicious extracted artifact high 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.
  • 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.
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/2.8/
    • http://www.xfa.org/schema/xfa-template/2.5/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0003_000.js
cf77d304854592d852dd5427be8a26060b0fb34046a26d7a0d9a1727ec087248
pdf-javascript-stream PDF /JS object 3 at offset 0x409 15454 bytes
base26_stage_000.js
fc26cf86445c8ed4fe6aaa83eaee7a6b9de8ed1e907ca8c3ff5cdb61ff55e969
deobfuscated-js base26-decoded JavaScript (decompressed) at offset 0x60D 5883 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 45 eval/decoder/string-building token(s).