Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8d7af9b43208d7a…

MALICIOUS

PDF

33.8 KB Created: 2020-05-18 09:26:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d4192868c16d588c983c74d92dc05c02 SHA-1: b8f88f440bb86245d2b6320643e4d75be9c99f58 SHA-256: f8d7af9b43208d7a474e25316533b518d3fddcf10cd2a53350f4110ad306a9f4
94 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains a large number of external links, many of which are dynamically generated and point to PDF files with numeric slugs. The document body, though heavily obfuscated, contains a reference to 'vmware client integration plugin' and the authoring application 'wkhtmltopdf', suggesting a lure to trick users into clicking malicious links. The ML classifier strongly flagged this PDF as malicious, indicating a high probability of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 4

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://jrfinancialservices.org/uploads/1/3/0/4/130477064/130477064.html#vmware+client+integration+plugin
    • http://akupressur-therapie.ch/uploads/1/3/0/9/130969842/kepemutaduvim.pdf
    • http://wittycam.net/uploads/1/3/0/7/130776818/zireme.pdf
    • http://lesgarrett.com/uploads/1/3/1/0/131070105/sijuzufoxaw.pdf
    • http://shakemixandroll.com/uploads/1/3/1/8/131856389/vajuxir.pdf
    • http://mitzimileskubota.com/uploads/1/3/0/6/130604026/xowovig.pdf
    • http://energyfreelivingathome.com/uploads/1/3/0/6/130621465/kagenolibetem.pdf
    • http://shorelinetextile.com/uploads/1/3/0/2/130272880/45b6091.pdf
    • http://3to1experience.com/uploads/1/3/0/7/130776819/kijusopuv.pdf
    • http://jimsvan.com/uploads/1/3/0/3/130312980/13be56080bb1b6a.pdf
    • http://echoesinsilence.com/uploads/1/3/1/4/131455543/60ad5a56.pdf
    • http://jamessanders.info/uploads/1/3/0/7/130775817/5246475.pdf
    • http://3strandedcord.com/uploads/1/3/1/3/131383928/guvowir.pdf
    • http://exclusivepropmgt.com/uploads/1/3/0/7/130775085/6669193.pdf
    • http://alanajaneskincare.com/uploads/1/3/1/4/131407736/godakogetokoluwuw.pdf
    • http://anynumberofbirds.com/uploads/1/3/0/5/130588547/narixonikoze.pdf
    • http://carolinascoastalconstruct.com/uploads/1/3/0/5/130588821/nagagularudenad-xorilej-siledelidajon.pdf
    • http://envpsintraining.com/uploads/1/3/1/4/131437275/bizufujuxil.pdf
    • http://happycard.com/uploads/1/3/1/6/131606583/f0a72a5d991.pdf
    • http://frenchsingaporemath.com/uploads/1/3/1/3/131383294/4d079026e626e2a.pdf
    • http://projectfloyd.org/uploads/1/3/0/6/130621928/jibez.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005a6a.bin
c28df53341f1460e17303f406e59b9dfb3c3dd474aeb957cff83b6896e34b1b8
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A6A 9664 bytes