Malicious PDF — malware analysis report

Static analysis result for SHA-256 17f1847b5913fe53…

MALICIOUS

PDF

104.9 KB Created: 2021-09-13 00:05:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a61ba0df6032a7ed5acda1e7e2aef741 SHA-1: 5be03700ce933d40301c3a66ff73d11a0a55ca69 SHA-256: 17f1847b5913fe53c458139584e7dee7c30cc36e9aa4f0ae3ae612381e2621a1
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure itself does not contain readable content, but the presence of external links and the high confidence detection scores strongly suggest it is used as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9877

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://crewmak.ru/uplcv?utm_term=time+management+games+android PDF link annotation
    • http://agisinfo.ru/uploads/content/files/29350719477.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/eaeb177fd98190fca2662294e7f94710/medanigalukesutesabofate.pdfIn PDF document text
    • http://intelekt.biz/uploads/pages/files/6015891705.pdfIn PDF document text
    • http://www.insight-assessment.com/ckfinder/userfiles/files/94864505700.pdfIn PDF document text
    • https://gonguyenkhoi.vn/upload/files/koredoxutigamoseti.pdfIn PDF document text
    • http://saraya-shop.ru/upload/files/debinik.pdfIn PDF document text
    • http://balone.net/_upload/file///69096095513.pdfIn PDF document text
    • http://articolo17.it/siti/usr/foto/files/vulupowefazuno.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ee3fcb868---nuwek.pdfIn PDF document text
    • https://biorenta.lt/ckfinder/userfiles/files/91228839671.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130272565031---xebotawusosewakor.pdfIn PDF document text
    • http://citescolairedeledit.com/include/file/19753990568.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/446b24f601c6d125df0e54e0c7e6aa37/76673367887.pdfIn PDF document text
    • http://petukmahaaaraj.com/userfiles/file/lukotudefarenarosifedo.pdfIn PDF document text
    • http://iiiemjobs.com/FCK_Editor_Images/files/waxukemovedejafosun.pdfIn PDF document text
    • http://eaas-journal.org/survey/userfiles/files/leguledarexowuneribibi.pdfIn PDF document text
    • http://highlander-inn.com/assets/userfiles/files/zajoxokewasomaritujad.pdfIn PDF document text
    • http://prabashproperties.com/ckfinder/userfiles/files/wamozawarewogobapofobil.pdfIn PDF document text
    • http://servmed.net/userfiles/file/fepewikijisakuninitusir.pdfIn PDF document text
    • https://aptitudeclass.com/ckfinder/userfiles/files/82253762826.pdfIn PDF document text
    • https://horacebatten.com/ckfinder/userfiles/files/29171733823.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/60041540007.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/998c590294c31254ec9dc89ad8e77993/7709216748.pdfIn PDF document text
    • http://abwingscolley.com/uploads/files/talurogewefasogavawolep.pdfIn PDF document text
    • http://kunjipsc.com/uploads/files/darilopudobufegiruzesotaw.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/lixud.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_off00013423.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13423 19084 bytes
SHA-256: 0018d0cbee5672024ee74ed476af4d03af09e94c092458c178806b437904c6ea
font_01_sfnt_off000165c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x165C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00017dd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17DD7 10508 bytes
SHA-256: 6045c90f056c38517c51043c76de166fbcb3907ba62eeabe134645fec08381a8