Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3d0b55e659ad407…

MALICIOUS

PDF

87.0 KB Created: 2021-09-14 04:13:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 53e9a179b192d0bea48985645cc77e0e SHA-1: adb14ccbc0033c41f7c52afefee4354a1cb45dc5 SHA-256: f3d0b55e659ad40744a6ee21deee0d128e8d264dfc2b22019e6b959108e0accb
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to domains that appear to be part of a link farm, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the nature of the URLs and the PDF structure point towards a phishing or spam campaign designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://laptopplus.be/app/webroot/files/userfiles/files/teferaxewizoxafosujabula.pdf In PDF document text
    • http://stonestudio.pl/files/upload/file/16812838938.pdfIn PDF document text
    • http://risme.vn/files/kupodij.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/fijofagidonipegesewopod.pdfIn PDF document text
    • http://www.s-prom.si/fileupload/file/25206327390.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/baxugilolujurazop.pdfIn PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/5334174515.pdfIn PDF document text
    • http://www.macrolepidoptera.hu/userfiles/files/48640553935.pdfIn PDF document text
    • http://nasledie-sluck.by/var/upload/file/mukitedebuvukuwojopomona.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/78680127099.pdfIn PDF document text
    • https://inprovitcolombia.com/ckfinder/userfiles/files/buwidunirurigiri.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/zelezebev.pdfIn PDF document text
    • http://rkenterprisesonline.com/FCKeditor/file/bixitemusi.pdfIn PDF document text
    • https://photopoligrafic.ru/ckfinder/userfiles/files/tifizuzataxizikagamixuved.pdfIn PDF document text
    • https://drnanemilk.com/tctt/sites/aaa/file/jolubusirawafikutegisof.pdfIn PDF document text
    • http://merklink.nl/site/data/ws/files/pifevogulanebu.pdfIn PDF document text
    • https://maintogelonline2.com/contents/files/78347058902.pdfIn PDF document text
    • http://netcentricnj.com/ckfinder/userfiles/files/dinumonomapejegexe.pdfIn PDF document text
    • http://laboratoriologos.it/userfiles/files/29811498392.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/52468815656.pdfIn PDF document text
    • http://prabashproperties.com/ckfinder/userfiles/files/zagulodolivulevu.pdfIn PDF document text
    • http://umbabox.com/userfiles/file/pevuzojibonuxutam.pdfIn PDF document text
    • http://akademibt.com/resimler/files/xenuxevu.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613db6f68947a---benep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=john+milton+books+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_off0000efb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107CA 18304 bytes
SHA-256: 7ef64b3fad6f4f187441366669d7a048a31e12b0f52bd35016a34ed082b4be29
font_02_sfnt_off0001373f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1373F 10592 bytes
SHA-256: 040c6ef3062b1be911506fb91d34b5bf17dc83cbe1ba1571118f2b69ba5d1e5d