Malicious PDF — malware analysis report

Static analysis result for SHA-256 d11aae1a7a805478…

MALICIOUS

PDF

93.1 KB Created: 2021-08-14 07:29:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: d6c1ecb54538a8dba9c25dc009857a18 SHA-1: 0382a0f9789e59fc6e7d52976d9a379243ecf52d SHA-256: d11aae1a7a805478d369631a1d95e0586b1f6e10b6d0ddb5cd5a7cd78eb48b50
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with heuristics indicating it functions as a link farm. Several extracted URLs point to compromised CMS upload directories or disposable hosting, suggesting an attempt to lure users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific intent beyond the link farm behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://novussiteyonetimi.com/uploads/file/mirimikimikezepitaj.pdf In PDF document text
    • https://europawindow.com/app/webroot/img/main_content/files/kesigejebuxejekelewit.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b071f22b53b---69070141512.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/56038464958.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/d3267da4201e6033e06efa2d898c35f5/waket.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608583154f64f---2770682962.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/xezogusixavizaluvox.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/e9a3304631324ac212fdf6c3f5a224fe/betujusumukixenumomamemig.pdfIn PDF document text
    • http://linkingpeople.info/userfiles/file/87181025614.pdfIn PDF document text
    • http://studiotecnicoprato.eu/userfiles/files/nuladizeguregatu.pdfIn PDF document text
    • http://interface-referencement.com/userfiles/file/kuvesuluminexulelo.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/85021661809.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/pizevubakanuvujojeginaga.pdfIn PDF document text
    • http://weiken-rc.com/upload/files/85221518807.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/15057495117.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/xupofazakuvaro.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/kubujevekofokeguwixiwe.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/23231326353.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021072606165548.pdfIn PDF document text
    • http://srub-servis.ru/userfiles/file/vupavumaz.pdfIn PDF document text
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/c27496fdd17c857992b41d046c5ad2c6/10586086548.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/de53631c4e03a71037b6bdcf49868977/fedekefepiwu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=composition+and+empirical+formulas+worksheet+answersPDF 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_off0001012f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1012F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011941.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11941 18380 bytes
SHA-256: 30674bccc2c361cd0f3b9ece77d9c9d293c24305b0fdf51dc6b5ba16312e6970
font_02_sfnt_off000149ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149EC 11192 bytes
SHA-256: e825b5368e270c533e0f144567e563feaeeb9919601121b493ccacb2cf771918