Malicious PDF — malware analysis report

Static analysis result for SHA-256 e21592687c4e5dce…

MALICIOUS

PDF

88.5 KB Created: 2021-10-18 08:54:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: dbf8ab846a23c105610a4266dbc5d542 SHA-1: ce7c40db679de1af8491a50c9c1b283b7f87f2b1 SHA-256: e21592687c4e5dce27000948537d7f75189d124601d76e9e92ff9b959bb18f38
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable or compromised domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://svx.su/ffile/file/sulakulojitet.pdf In PDF document text
    • http://atol-res.pl/uploads/file/38316311221.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131315dbd852---xejudabigubepudu.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/64732950776.pdfIn PDF document text
    • http://pyramidplaster.com/file_media/file_image/file/70065912258.pdfIn PDF document text
    • http://kkagro.com/media/images/upload/file/56128246118.pdfIn PDF document text
    • https://questyme.ca/userfiles/file/befeka.pdfIn PDF document text
    • https://marblo.ph/app/webroot/img/files/76292820979.pdfIn PDF document text
    • https://yasacompany.com/upload/files/jirobaradizorula.pdfIn PDF document text
    • http://zulaikhatextile.com/userfiles/files/loporamipuju.pdfIn PDF document text
    • http://spbmedaks.ru/sites/default/files/uploads/25559006223.pdfIn PDF document text
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/24233665252.pdfIn PDF document text
    • https://monyetjoget.com/contents/files/kupuvikomukobotutim.pdfIn PDF document text
    • http://nakloboucku.cz/uploaded/file/18610951444.pdfIn PDF document text
    • https://joinvita.com/neu/userfiles/file/26586990116.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/d07ecf58197a851949aacb869ee2675f/60935344245.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132723584b37---99226625679.pdfIn PDF document text
    • http://simonkuehner.de/gfx/userfiles/files/36812236820.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/dcu5bqei64sn1es5793eej97ms/90719277205.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/16720333997.pdfIn PDF document text
    • https://tranhtreo.com/images/ckeditor/files/jugelezubuzora.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/xPAns0MRe5M/uplcv?utm_term=watch+broly+movie+online+freePDF 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_off0000f57e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF57E 10748 bytes
SHA-256: 29fe25a38926fd2c2a19b2153db4118df535e220f8ff736d7765607eb108129a
font_01_sfnt_off00010e0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001261f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1261F 17804 bytes
SHA-256: 9e6939a132e01535b3bb964cccf013f9c477c4340897cde5da5e41d56dfcfd41