Malicious PDF — malware analysis report

Static analysis result for SHA-256 0350bb526dc651cf…

MALICIOUS

PDF

76.3 KB Created: 2021-09-06 10:27:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 45acffbe86967a3155ecf48977e68f0e SHA-1: 0912472009a4258a7940dafed95cdeaf8d028a46 SHA-256: 0350bb526dc651cf1b1cbd70a9f9ecb54297e3e352f1d91927f6ff90664146a2
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://sshs1962.info/clients/3/33/33dcd814b32da85629335a95ab3d0158/File/kigizabazupozepu.pdf In PDF document text
    • https://fertilizergranulatorprice.com/d/files/44699082048.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/81783333051.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/402f3ac29b0c7a2d49693b60f52fb7a1/banajabidunilonenaf.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/jusarisuduxevabozonano.pdfIn PDF document text
    • http://wjvanderheidedienstverlening.nl/uploads/file/51326517158.pdfIn PDF document text
    • https://aslplastic.com/ckfinder/userfiles/files/94906910275.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16071e4420ba50---nolomisag.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070b40869aaa---kukabumakubupubalisos.pdfIn PDF document text
    • https://castilloexterior.net/ckfinder/userfiles/files/pebofadudolisutewivo.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/boginu.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/aa72669a571164e6f45708e3bec24d28/26106695734.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021051723091862.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608b9c73b4250---73999057398.pdfIn PDF document text
    • http://tms-operation.com/upload/files/mozudagejidulodefiwudep.pdfIn PDF document text
    • http://drironcat.com/images/file/vajunifune.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/boxatawirumewefiregaked.pdfIn PDF document text
    • http://srsheicha.com/uploadfile/file/sudarajapef.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608a968b64d7d---lojapejoxigiwoxez.pdfIn PDF document text
    • http://chronicles.ae/userfiles/files/22110100289.pdfIn PDF document text
    • http://teckim.it/themes/userfiles//files/80300694083.pdfIn PDF document text
    • http://taperagi.com/contents//files/88849952162.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160866f812ffd3---wurejabadirexufinomazedu.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/nonipumisukijukuzaje.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=farmacognosia+capasso+pdfPDF link annotation
    • 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_off0000c6f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6F5 17308 bytes
SHA-256: 91534f1a0510e0bcad5c3731866c0995a298ce7d0555d44f7e63ba19c7cb7377
font_01_sfnt_off0000f36e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF36E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B85 10664 bytes
SHA-256: b165a4435e29e763cf78394e7a7823769631bbbbb0550675793fddbc029598f3