Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6751a58c75fac8b…

MALICIOUS

PDF

88.0 KB Created: 2021-09-23 17:06:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: aa71cbbbbad07155e6bf93ad8e656774 SHA-1: b29d5adaf58fd73b938e250a08f02280a308d710 SHA-256: f6751a58c75fac8bdb6221e4b68648d112dafcbb79d0b941abf46154d022d814
134 Risk Score

Malware Insights

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

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm with numerous embedded URLs, likely intended to direct users to malicious sites or download further payloads. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://huntic.ru/uplcv?utm_term=redmi+note+7+havoc+os PDF link annotation
    • https://mmeasar.com/mmeasarfiles/file/5721195959.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/dogalul.pdfIn PDF document text
    • http://bonfiremadigan.com/uploads/fckeditor/file/21041408032.pdfIn PDF document text
    • http://indcms.testingmachines.com/images/file/54862546221.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/90700005019.pdfIn PDF document text
    • http://bretagne.annuaire-regional.com/ckfinder/userfiles/files/zubedumakulo.pdfIn PDF document text
    • https://istanajp2.com/contents/files/vuzop.pdfIn PDF document text
    • https://plantbiochem.com/ckfinder/userfiles/files/33596547019.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/66309878616.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/finokolevozozuzaxu.pdfIn PDF document text
    • http://telecycling.info/files/file/60157426266.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/mirox.pdfIn PDF document text
    • http://outspokenholland.com/userfiles/fckFile/20210914045130.pdfIn PDF document text
    • https://lifo-sea.com/ckfinder/userfiles/files/zawugetubejofadebituku.pdfIn PDF document text
    • http://timavoshipsupply.it/userfiles/file/ruwibafoxamesuko.pdfIn PDF document text
    • http://1yunnan.com/ckfinder/userfiles/files/90292993032.pdfIn PDF document text
    • https://indolabtek.com/Uploads/userfiles/files/37171170071.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612f16d0e5515---mutubu.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/zuvodivagafas.pdfIn PDF document text
    • http://laptopplus.be/app/webroot/files/userfiles/files/fevisuzukadobixujo.pdfIn PDF document text
    • http://exito-opakowania.pl/userfiles/file/wukisoduwopozubuvuxa.pdfIn PDF document text
    • http://donovaly-ubytovanie-safran.sk/web/userfiles/file/63176052467.pdfIn PDF document text
    • http://pttaccounting.com/userfiles/files/kugutegipaverawixatasil.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135761c3770f---tejagupumepakujiwado.pdfIn PDF document text
    • http://positiveforce.in/uploads/files/32258785168.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_off0000eb0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB0D 21252 bytes
SHA-256: 31368e717ec0bc1be519b1b21551bbfa211f1dbaf372a193f943f2a461783a53
font_01_sfnt_off000121c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121C1 10652 bytes
SHA-256: 2de95dd5a3f3be46986f5cb2096c85695baad10059831c65811f4a8aed590f7c
font_02_sfnt_off00013a15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1