Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9726fb172c41786…

MALICIOUS

PDF

69.7 KB Created: 2021-09-28 17:54:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 9ab7fff24d3a6d8b53b7979f5e52846c SHA-1: 89b51c291edff00145692084dcb4eb45fa1e07b7 SHA-256: b9726fb172c4178613fc80d8df86705a8727ce710522cc00a88462a6c9def00a
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by an ML classifier. It contains numerous embedded URLs, with one heuristic identifying it as a link farm on disposable hosting. The presence of external URIs and the structure suggest an attempt to direct users to a network of sites, potentially for SEO abuse or to host further malicious payloads. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 4

  • 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://velomagazin.hu/UserFiles/file/sutobuki.pdf In PDF document text
    • http://maychebiengoduykhuong.com/media/ftp/file/setolefuteferosef.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/xeriloka.pdfIn PDF document text
    • https://travelworld.ro/userfiles/file/wujupuvumijivalubifapuvu.pdfIn PDF document text
    • http://www.kizkulesikizogrenciyurdu.com/public/ckfinderuploads/files/19657411258.pdfIn PDF document text
    • https://www.funes.gob.ar/ckfinder/userfiles/files/xalosupufixudeguvawawol.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/pediwudiwafowopu.pdfIn PDF document text
    • http://s2group.pl/userfiles/file/14572224738.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/30164587751.pdfIn PDF document text
    • http://industra.sk/userfiles/file/basidifebafilafiga.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210904_012356.pdfIn PDF document text
    • https://careersourcechipola.com/files/public/74336148878.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/xiluza.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/koven.pdfIn PDF document text
    • http://hertzlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/64588189982.pdfIn PDF document text
    • https://sesconbs.org.br/ckfinder/userfiles/files/37878503905.pdfIn PDF document text
    • http://oshcongregation.com/userfiles/file/zozajavosasuresera.pdfIn PDF document text
    • http://dd-eng.com/files/files/70510750830.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/894dd9db1268a8891880ba5a25f1dbea/ferovaxewexinuturobosul.pdfIn PDF document text
    • http://epplast.com/files/file/vulepam.pdfIn PDF document text
    • http://unseretochter.com/images/file/13639343329.pdfIn PDF document text
    • https://enkaotomatikkapi.com/depo/sayfaresim/file/76080946594.pdfIn PDF document text
    • https://phoenixturkey.com/upload/ckfinder/files/80078021463.pdfIn PDF document text
    • https://10fci.org/userfiles/file/95348228588.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/78187661e79254c24f7d532fcc8dd6ed/jowesutofe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=kingroot+apk+7.0+downloadPDF 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_off0000b145.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB145 10676 bytes
SHA-256: 61d347fc37f298bc752f576c1c13e0cd07be69e311d8d6aac8a4cb514d9ccf5b
font_01_sfnt_off0000c9ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e1c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1C0 15580 bytes
SHA-256: e6e6df3198e525fd8cac76ddef6343b5767d7e5ef4960dd40e2bc4dc2e6ed0f7