Malicious PDF — malware analysis report

Static analysis result for SHA-256 5aa156d5e5005b72…

MALICIOUS

PDF

89.2 KB Created: 2021-09-10 03:25:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 31b8c7f2219a00033dd3bf8eefb29caf SHA-1: 96530d4e734eca3ae4d44afadb5c5ebc3b041896 SHA-256: 5aa156d5e5005b72ad04a40ca7488b035fc515557a9060b62d3356e73a036a67
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. The presence of numerous links to potentially malicious sites suggests an attempt to lure users to phishing pages or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 https://queure.ru/uplcv?utm_term=redmi+note+9+stock+android PDF link annotation
    • http://abwlargo.com/uploads/files/zejaboposuwugor.pdfIn PDF document text
    • http://yenidenyuzlendirme.com/ckfinder/userfiles/files/7566446714.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/fm0hqav6h7vgl8oa67pmpi0s2k/xirepemadaxados.pdfIn PDF document text
    • https://volgogradexpo.ru/ckfinder/userfiles/files/vanuzame.pdfIn PDF document text
    • http://cristal-in.fr/userfiles/file/xipuxuriladolu.pdfIn PDF document text
    • https://cjsc.se/ckfinder/userfiles/files/woror.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/jrknio60c2uqkau9tlscmtfjpu/89515646052.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161377c281c0c6---18532709975.pdfIn PDF document text
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/35733805336.pdfIn PDF document text
    • https://kokomanis.com/contents/files/53661798345.pdfIn PDF document text
    • http://sin-hua.org/userfiles/natola.pdfIn PDF document text
    • https://beyondpins.com/calisma2/files/uploads/30590447490.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/logob.pdfIn PDF document text
    • http://ailizia.com/userfiles/43468363564.pdfIn PDF document text
    • http://molenat-energies.fr/molenat.com/images/editor/file/kufeworutusedukabagesijiv.pdfIn PDF document text
    • https://inprovituruguay.com/ckfinder/userfiles/files/71748162543.pdfIn PDF document text
    • https://ngonluathan.com/images/ckeditor/files/52171837494.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135d104006fa---48584807303.pdfIn PDF document text
    • http://solarwindependence.com/ckfinder/userfiles/files/10377936695.pdfIn PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/zejanowolozolatamubejapa.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f69ef4b696---dosojerugodulefakima.pdfIn PDF document text
    • https://girilawfirm.com/content_files/files/tafowunibalit.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f65b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF65B 18644 bytes
SHA-256: 2864448ff5f2a57f25cae1d0fe1a897fa6feedc8f5b077c2a77997483bcca62f
font_01_sfnt_off00012656.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12656 10792 bytes
SHA-256: ac71ea8fa332dc384bdbd0ac93ee1d67942f91a4f8bfcc245ded7b4299efdca1
font_02_sfnt_off00013f42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1