Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f703e1dda776cc8…

MALICIOUS

PDF

88.3 KB Created: 2021-09-09 19:51:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-16
MD5: 783be6099fd777bbff511cfd89e6b48e SHA-1: 0a72ae8cb82ac99ee8f7ddb5471acaa31b1eef6d SHA-256: 5f703e1dda776cc84ae14040e4dbd853adbbb7d90b9e40f7d237739e47b3385a
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The file functions as a link farm, containing numerous URLs that point to compromised WordPress upload directories and other disposable hosting. These links likely lead to further malicious content or phishing pages.

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://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135f63e4a4ce---16703129956.pdf In PDF document text
    • https://khangle.vn/uploads/images/files/29745085120.pdfIn PDF document text
    • https://euroroma-bg.org/files/file/79546406169.pdfIn PDF document text
    • https://tuoitre.bacgiang.gov.vn/lib/ckfinder/files/88402199738.pdfIn PDF document text
    • http://thibidi.vinadesign.info/uploads/images/files/32776251915.pdfIn PDF document text
    • http://contextuae.com/resimler/files/bemab.pdfIn PDF document text
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/bovegaxow.pdfIn PDF document text
    • https://sapporopools.com/contents/files/notisabosimip.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/09/08/file/zerimuwagutebuboridad.pdfIn PDF document text
    • https://shatalarab-llc.net/userfiles/files/52204068456.pdfIn PDF document text
    • http://denkobarbell.com/_upload/files/golemexadojejilek.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613058b7cb6e5---36624651343.pdfIn PDF document text
    • https://xistenze.nagydavid.com/files/files/sunomixosubugenofenoxu.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/4f53443d875a624c71af6a795558900b/sokowolafovoxitijurov.pdfIn PDF document text
    • http://xn--22cjbbm2eyae3ehabdb4kqdtae3dxnnc1fhf.com/user_img/files/botevapoketabowomigek.pdfIn PDF document text
    • http://tinavaron.com/ckfinder/userfiles/files/6645713603.pdfIn PDF document text
    • http://hoangminhphatkorea.com/webroot/img/files/defoj.pdfIn PDF document text
    • https://wisestudentz.com/userfiles/file/94968409294.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16134ae0acc51a---89997901962.pdfIn PDF document text
    • http://gtlfuelmarine.com/userfiles/file/53931447355.pdfIn PDF document text
    • http://quiltingacademy.com/fckeditor/userfiles/file/96011305.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/kolegex.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/49384259645.pdfIn PDF document text
    • http://mcrlclient.gilcom.ro/ckfinder/userfiles/files/73918672137.pdfIn PDF document text
    • http://baracenter.be/userfiles/file/wezaburezurugat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=retro+game+center+androidPDF 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_off0000f769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF769 10544 bytes
SHA-256: 7e8fcf3683ef754f2042b4aa6953994ce2bd095eca9f1340540abe38b2696ba3
font_01_sfnt_off00010f38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F38 17004 bytes
SHA-256: 45eabebc403124801ccf367c7cebccaa177ed0cf2399caa73a24f42f2d3548ee
font_02_sfnt_off00013b9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B9E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1