Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b390b839dd71bad…

MALICIOUS

PDF

77.1 KB Created: 2021-09-16 19:51:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a22a6953ac30016dbc883352cec22f53 SHA-1: 0f5ed31d311b4bc600c491a21113b20166fce104 SHA-256: 8b390b839dd71badc7d915f365991314a3b1fd8891314da01c9e75487cf5a1db
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Several heuristics point to the document being a link farm, with many URLs hosted on compromised or disposable domains, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the nature of the URLs and the detection indicate it likely serves as a lure to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://ngor2-3.com/file_media/file_image/file/fabevuxopodezesagidewelin.pdf In PDF document text
    • http://studiogiovannone.com/userfiles/files/sodebugimorakosu.pdfIn PDF document text
    • http://artin-intranet.com/ckupload/files/bivuj.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/kupade.pdfIn PDF document text
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332753517fb---zofutute.pdfIn PDF document text
    • http://batterseataxi.com/survey/userfiles/files/zozezibux.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/lopebubuwezirufujepogof.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/527349610.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/batapi.pdfIn PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/gawogulunuresito.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/46151327063.pdfIn PDF document text
    • http://yogaschoolofkerala.com/photos/editor/files/89685111376.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/40505479445.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/sozokizafoja.pdfIn PDF document text
    • http://plkorea77.com/ckupload/files/39865495286.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16139edd73fe49---5889934046.pdfIn PDF document text
    • http://www.tivafa.hu/upload/file/64793265544.pdfIn PDF document text
    • http://theffirm.com/userfiles/file/foguposakon.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393d0d283b6---getenekukedugaso.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/63392409610.pdfIn PDF document text
    • http://advocaatindex.nl/images/uploads/berosarawave.pdfIn PDF document text
    • https://valerart.com/ckfinder/userfiles/files/1669199389.pdfIn PDF document text
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/64436036263.pdfIn PDF document text
    • http://bladensburg.abwingsmd.com/uploads/files/gomuwogenakunojom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=caperucita+roja+cuento+corto+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_off0000c669.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC669 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000de7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE7B 18784 bytes
SHA-256: 8886e34e02571c1291ce31b03eeedcd81da0ff4b932ac724ddf434c10bce0668
font_02_sfnt_off00010e48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E48 10660 bytes
SHA-256: 94f174c03b066881b9770b00d127202e9af5bc7c012e96cb59fdbc155ebcc779