Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac00acff0ffe76c0…

MALICIOUS

PDF

94.5 KB Created: 2021-09-07 07:16:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: ab68f4fc55ba2a285531afd1e0a517cd SHA-1: be7769532361f219a971eda271ab91fbe14a576c SHA-256: ac00acff0ffe76c0e172fc7cb6d00b66c4ab13bb07b0c1e6939c8df0136508f7
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • 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://medosojewellery.com/userfiles/files/zapajujatudotinol.pdf In PDF document text
    • http://tikatalog.sk/_files/file/tasosam.pdfIn PDF document text
    • http://zdravi-kromeriz.cz/files/file/25027926403.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609dc5cd3b28e---babivuzeririk.pdfIn PDF document text
    • https://nocenzura.space/web/img/podborky/files/xemumifamizazudor.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/b00d404d1bf5a376359db755e1288104/jimiserarupomi.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b20e44164a7e915297d4213c000ca107/78385364023.pdfIn PDF document text
    • https://ambulatorioveterinariosismondi.eu/file/3431593672.pdfIn PDF document text
    • http://knshzj.com/CKEdit/upload/files/pakepokasofuf.pdfIn PDF document text
    • https://ambulatorioveterinariosismondi.eu/file/lexuva.pdfIn PDF document text
    • http://xn--o79av69abka850ab6c.com/upload/file/202105310924233788.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16121095d82c4d---liporuvujugen.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/4dea42f79b110761354fee04c4724aa9/xolipokujuxugudukupubenar.pdfIn PDF document text
    • https://dm288.com/slicice/file/pexaxoke.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/lusigewazemipirepik.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/97591441150.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/tisiditibapeselivo.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/sirubi.pdfIn PDF document text
    • http://kukdae.com/files/fckeditor/file/ritudazalixolop.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/0491c6cacea787d7a1b2d3787d7f151b/81670262728.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160e10907174c2---38768546026.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bac8de82857---zovasepap.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef86ae6d73---19442090609.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16123dfa62cfaf---16974994841.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=land+rover+discovery+2003+owners+manualPDF 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_off000106a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A5 19488 bytes
SHA-256: f84bd04e0d51b876806c0c806b11ff13a8c20a273c3453dfbb747695ae8cab6f
font_01_sfnt_off000139ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015216.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15216 11168 bytes
SHA-256: 868d49b14484570540599078d2805c2c1965b75172ce07183baa55852b83db39