Malicious PDF — malware analysis report

Static analysis result for SHA-256 169f3560d878a77f…

MALICIOUS

PDF

77.6 KB Created: 2021-10-01 07:17:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 574ccba0e2b5a7d88cd5e0ef7bd4dfba SHA-1: 6beb51d9963c891c925dea730dde2fc736cf5e2b SHA-256: 169f3560d878a77f90e752e424446f6b057044d7e186cfd44d3baa0bff2fdf0d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the embedded URLs and link farm structure are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://trungnguyenjsc.vn/uploads/image/files/rezelewajajiwil.pdf In PDF document text
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/45897674830.pdfIn PDF document text
    • https://komunalno-vrgorac.hr/files/mukasapulamopafoporexaf.pdfIn PDF document text
    • http://klm-co.ru/foto/ck/files/91955996740.pdfIn PDF document text
    • http://cheniou.handysociality.com/upload/files/1853626452.pdfIn PDF document text
    • https://kaowei.tw/image/files/20210908_032540.pdfIn PDF document text
    • https://ltes.tw-goods.com/UserFiles/files/81209551482.pdfIn PDF document text
    • http://asremajazi.com/uploads/files/67559119901.pdfIn PDF document text
    • http://ventexevent.se/uploads/file/20899301550.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/161416272a0c87---30526166160.pdfIn PDF document text
    • http://cottoneauto.it/userfiles/files/64268922285.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614b8910ca94e---33296984235.pdfIn PDF document text
    • http://gesht.ru/admin/ckfinder/userfiles/files/samolute.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/214e6adacd544419c83192fead70a7d9/zodozafipezepu.pdfIn PDF document text
    • http://cascad-trans.ru/files/4267079730.pdfIn PDF document text
    • http://htwy.com/upload/file/zekapajerotepapavofa.pdfIn PDF document text
    • https://www.whoamiandwhyamihere.com/ckfinder/userfiles/files/josenazegej.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145853bce4f8---ziravivawulabusesapek.pdfIn PDF document text
    • https://cleanenergy.mn/uploads/files/31832334468.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/45346247593.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/20338086249.pdfIn PDF document text
    • https://slide-bearing.com/d/files/jekosubixamowogonet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=hanuman+chalisa+by+english+devoteesPDF 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_off0000c416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC416 11128 bytes
SHA-256: 7b8c21a827f9c9c91baad147eddbee31a9773e77a74174116e63a245632a6480
font_01_sfnt_off0000dda2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B4 19524 bytes
SHA-256: 9dd9f4ceaabcad047f2a1069f3a3e3637b7493302ead5ce55ef624823d96d894