Malicious PDF — malware analysis report

Static analysis result for SHA-256 52e9414d67bf14af…

MALICIOUS

PDF

71.6 KB Created: 2021-09-17 01:56:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 710c49b0916e3f1a101e19c68753b135 SHA-1: 33ae477c007f05ff752251f54ec49a27d2e7bc23 SHA-256: 52e9414d67bf14aff8f725dc1d1971f219d51b873f766c3a2b6ec355a7f94be3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, containing numerous external URIs pointing to other PDF files hosted on various domains. The primary purpose appears to be directing users to these external resources, which could be for SEO manipulation or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://www.theknowledgeonline.com/files/lib/ckfinder/userfiles/files/98324410661.pdf In PDF document text
    • http://zulassung4you.de/bilder/file/71356908523.pdfIn PDF document text
    • http://landonintergroup.com/ckfinder/userfiles/files/11772740554.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/161381f4ea57ac---najifuzumajawefewexupo.pdfIn PDF document text
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/30329680726.pdfIn PDF document text
    • http://ahdjcm.com/upload/files/65956649773.pdfIn PDF document text
    • http://dlzhrjd.com/images/uploadfile/files/20074330051.pdfIn PDF document text
    • https://hostsolutions.ro/app/webroot/files/userfiles/files/vixaw.pdfIn PDF document text
    • https://bodykneadstherapy.com.au/ckfinder/userfiles/files/61747640598.pdfIn PDF document text
    • http://przystaneknida.pl/data/aktualnosci_imgs/file/46805921942.pdfIn PDF document text
    • http://chocoenglish.com/_UploadFile/Images/file/jusevigiwemafajebun.pdfIn PDF document text
    • https://autohausnschmidt.de/userfiles/file/88389852902.pdfIn PDF document text
    • http://xn----7sbndn5at.xn--p1ai/uploads/files/60701586671.pdfIn PDF document text
    • http://drivescuolaguida.it/userfiles/files/fexifakurakoza.pdfIn PDF document text
    • http://taiwanquinoafamily.com/shopadmin/upload/files/rajamemorujaribikefa.pdfIn PDF document text
    • https://euro-m.si/web/dokumenti/file/kadodibofonewu.pdfIn PDF document text
    • http://uelzecht.lu/userfiles/files/22088350296.pdfIn PDF document text
    • http://domusanna.it/userfiles/files/befidetemoxuka.pdfIn PDF document text
    • http://df-2.de/images/daten/file/zudeju.pdfIn PDF document text
    • https://vegastel.eu/components/com_mijoshop/opencart/image/data/files/kodewasozomuxabepo.pdfIn PDF document text
    • https://riosemarescentrodemergulho.com/ckfinder/files/55690054373.pdfIn PDF document text
    • https://autotronics.vn/userfiles/file/pefefazotamumikawujek.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/36250855827.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=technical+analysis+of+stock+trends+free+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_off0000b51d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB51D 16552 bytes
SHA-256: 80f0b249209d100a28c136d790ceddb164b2c60df77cf928f6afdf98702078ea
font_01_sfnt_off0000df61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f778.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF778 10884 bytes
SHA-256: 0db77f56c967036aa31cfc6e0a0351bdc53582fb70fd683faaea945643a47d0e