Malicious PDF — malware analysis report

Static analysis result for SHA-256 aaf983e440171e72…

MALICIOUS

PDF

81.8 KB Created: 2021-09-19 14:32:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8a9e3833e63d7b63e721456ddbbb32f1 SHA-1: 3809f5adde4cf925c8d33cf51863a68758f31d56 SHA-256: aaf983e440171e7299bfa689ed2e4cfd9296f0f26bbc25d7dd4f702e51ee83c6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports the conclusion that this is a link farm designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://inwebjor.ru/uplcv?utm_term=messenger+chat+heads+not+working+android PDF link annotation
    • http://yjccnc.com/upload/files/kifematasezajududu.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/reridumagaz.pdfIn PDF document text
    • https://hankilfood.com/upfile/files/kezonapizivenebadifajuta.pdfIn PDF document text
    • http://firmen-bekleidung.at/userfiles/file/feduvidofafapexepamunarid.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013/admin/ckfinder/userfiles/files/warubeb.pdfIn PDF document text
    • https://baglab.pl/galeria/file/mifunalajituse.pdfIn PDF document text
    • https://ecpa.fr/uploaded/file/60411134283.pdfIn PDF document text
    • https://cicadit.ro/UserFiles/file/8608249683.pdfIn PDF document text
    • http://skupka23.ru/upload/m/20652713270.pdfIn PDF document text
    • https://cicimanis.com/contents/files/wanabejenejovepenoxuvatu.pdfIn PDF document text
    • http://sostrevalli.it/userfiles/files/47326208557.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613697c4b1cf6---82000987044.pdfIn PDF document text
    • http://kutscher-customs.de/gfx/userfiles/files/6720647825.pdfIn PDF document text
    • http://colantuono.it/userfiles/files/supezumaxewatawijajumomim.pdfIn PDF document text
    • http://exosushi.com/uploads/files/17797046455.pdfIn PDF document text
    • http://feriaalainversa.com/uploaded/files/9358165847.pdfIn PDF document text
    • https://www.le-domaine-de-hauterive.fr/ckfinder/userfiles/files/78296867990.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/tifunugubakovanadopozok.pdfIn PDF document text
    • http://creatinglifeoptions.com/userfiles/files/navazitonakow.pdfIn PDF document text
    • http://meskerjager.nl/media/files/2636022475.pdfIn PDF document text
    • https://beautifulhairstore.com/upload/files/rexifajakisawugegizuj.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613905f71af9e---saborunewibavubitixakoz.pdfIn PDF document text
    • https://tsolisp.com/files/file/faxegumavipazove.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16139e9bf5f170---zijaparojupenuzu.pdfIn PDF document text
    • http://salukool.ee/upload/userfiles/file/mawubivijav.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_off0000d9fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9FD 10772 bytes
SHA-256: 4607e7cdab700aef275113288ade78ba6be2f7702187a4ed5fba11d612467510
font_01_sfnt_off0000f2a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A2 18100 bytes
SHA-256: 59902986b532dd02837367b06f846d916c244cb1b51c4122b9512b6dda2319ef
font_02_sfnt_off0001215a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1215A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1