Malicious PDF — malware analysis report

Static analysis result for SHA-256 919e1ea0811fc116…

MALICIOUS

PDF

84.7 KB Created: 2021-10-05 13:19:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 76f290ca9187f784647c13ef092263ec SHA-1: 793e1224abe3c2cd92f0b8aa4f9f77e7560443c4 SHA-256: 919e1ea0811fc11635040147982f359f72f07df3897b7ad8a7f65825692f9cfd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it with high confidence. The PDF contains numerous external URIs and link farm patterns, suggesting it is designed to redirect users to malicious websites. While no scripts were explicitly extracted, the PDF structure and heuristic firings indicate it likely exploits PDF vulnerabilities or uses embedded JavaScript to facilitate these redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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 https://krisoc.ru/uplcv?utm_term=how+do+you+spell+hi+in+russian PDF link annotation
    • http://worshipedia.net/sites/default/files/file/tuzukigokunesitazutonew.pdfIn PDF document text
    • https://digitaluzaktanegitim.com/calisma2/files/uploads/lekibexodosadixarofasa.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614769cf9f6be---24161275884.pdfIn PDF document text
    • http://anindecor.pl/files/file/lapunikuperudigi.pdfIn PDF document text
    • http://xdata.pl/app/webroot/img/ckf/files/67309481403.pdfIn PDF document text
    • http://tearose-kitchen.com/sites/default/files/images/imcefile/rulag.pdfIn PDF document text
    • http://birdwatching.sk/media/file/xukaz.pdfIn PDF document text
    • https://travelinnsuites.com/nbloom/fckuploads/file/23974808241.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1614020c6ce507---padok.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a84d6388bf---86313328531.pdfIn PDF document text
    • http://elliptical-trainers.ru/ckfinder/userfiles/files/talusepuzifok.pdfIn PDF document text
    • https://kiofruits.com/admin/uploads/files/pefaritefekimujovepa.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/mebififedirumina.pdfIn PDF document text
    • https://360clothing.in/home/www360cl/public_html/uploads/images/files/82250948267.pdfIn PDF document text
    • http://hoinhikhoavn.com/img/files/69402379418.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/dodugebovesaxu.pdfIn PDF document text
    • https://homeuu.biz/upload/ckeditor/pages/files/rufekiralususosipa.pdfIn PDF document text
    • http://greatwalledmond.com/ckfinder/userfiles/files/mesagukilijuziku.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/2894000172.pdfIn PDF document text
    • http://evevoyance.fr/adh/.-/file/1843122903.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/1202001995.pdfIn PDF document text
    • http://khocabien.com/uploads/files/somuboditozerad.pdfIn PDF document text
    • http://majortaylorride.info/images/uploaded/file/18434377971.pdfIn PDF document text
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/16344321096.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/80717506702.pdfIn PDF document text
    • https://postelezmasivu-liberec.cz/ckfinder/userfiles/files/zilezafugavukigi.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_off0000de01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE01 10680 bytes
SHA-256: ec1bd0a69b99e4ced2b1450823550f25ee4559c2351d2e7be50d4319b0f67644
font_01_sfnt_off0000f664.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF664 21460 bytes
SHA-256: 504eb2924a83a21d0de32b8ab6fb82502f78574a30d29c14af48091d4eebfb89
font_02_sfnt_off00012d19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1