Malicious PDF — malware analysis report

Static analysis result for SHA-256 318452d511f74a1e…

MALICIOUS

PDF

108.7 KB Created: 2021-09-10 22:10:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 37825c1f79d71c9fdd7eee465d4bd11e SHA-1: c8df3bdaa15ab2c87b4caf4f0c389e9611a4db5b SHA-256: 318452d511f74a1e0599be25bd5d1abdd047eadee2159bbc01633251f6bdad1e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many pointing to disposable domains, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests a phishing or malware distribution intent. No scripts were extracted, but the overall structure and heuristics point to a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9899

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kastely-vacduka.hu/fileok/file/xolederunedawezilesodet.pdf In PDF document text
    • https://iphone-odklep.si/vsebina/57294005259.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/wejetezebosusopu.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/12758001344.pdfIn PDF document text
    • https://partroyfuneralhome.com/partroy/assets/file/75394640661.pdfIn PDF document text
    • https://groupunsur3.com/contents/files/62419181393.pdfIn PDF document text
    • http://termocity.by/pics/files/dejipisedusijodesemus.pdfIn PDF document text
    • http://debeleven.net/UserFiles/File/20893705952.pdfIn PDF document text
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/wagogomupumamafelapadofo.pdfIn PDF document text
    • http://3e-machinery.ru/app/webroot/filesfiles/12261368202.pdfIn PDF document text
    • https://gencshoworganizasyon.com/upload/ckfinder/files/tevexe.pdfIn PDF document text
    • http://oresteruggiero.com/userfiles/files/14037428577.pdfIn PDF document text
    • http://lifecare4all.com/upload/files/xivelerukogijelurit.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/5772771274.pdfIn PDF document text
    • http://hoangnamjsc.com/upload/files/16649949006.pdfIn PDF document text
    • https://nocenzura.space/web/img/podborky/files/25904580531.pdfIn PDF document text
    • http://schokofontaene.de/idata/41602868575.pdfIn PDF document text
    • https://seerupit.dk/assens/file/85392903889.pdfIn PDF document text
    • https://chrmglobal.com/userfiles/file/voboxa.pdfIn PDF document text
    • https://studiovizia.com/webroot/img/content/files/mamixodovuwolofimisatake.pdfIn PDF document text
    • http://anbao.vn/uploads/userfiles/file/34506738738.pdfIn PDF document text
    • http://regcureguide.com/files/files/29418578228.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.com/ckfinder/userfiles/files/losokanaludul.pdfIn PDF document text
    • http://www.salac.cz/ckfinder/userfiles/files/66793855317.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=which+country+has+the+second+highest+population+in+the+worldPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00013d0d.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x13D0D 17944 bytes
SHA-256: 6005739ce26c6c062429f1cdab8c5e2d0a689d551a70d10d3b21928b3681d2a3
font_00_sfnt_off000124fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001590a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1590A 11088 bytes
SHA-256: 2a4cb69b15195efd0f5139240879154b5640dcb33f05331d7e8d671e9fa768ba
font_03_sfnt_off000172b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x172B1 18952 bytes
SHA-256: b66349e3047cb4ced995e6b22dd3490cbc5a357a194ca8447e0e196d39701031