Malicious PDF — malware analysis report

Static analysis result for SHA-256 58b30d88fb0caa2a…

MALICIOUS

PDF

79.2 KB Created: 2021-09-19 05:30:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: bfba819f229a2640136e064cc1456368 SHA-1: 2ad78b8903adbe810cdebbbdcaf5778379f09926 SHA-256: 58b30d88fb0caa2a047250562fc1698216285fb322fd29536ddbaf34d7afee0a
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to various domains, many of which appear to be part of a link farm. Several heuristics indicate that these links are hosted on compromised CMS uploads, suggesting a tactic to obscure malicious activity or leverage legitimate-looking infrastructure. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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 https://wastran.ru/uplcv?utm_term=how+to+install+imei+number+in+android+mobile PDF link annotation
    • http://playbabydoll.com/userfiles/file/bijegobitipegujuso.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///33281301082.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/66568834218.pdfIn PDF document text
    • https://univerosg.com/ckfinder/userfiles/files/84862935698.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/motunevix.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614073899056a---joxejoromubagufop.pdfIn PDF document text
    • https://impactmediaresources.com/userfiles/file/29186162355.pdfIn PDF document text
    • https://wojczak.pl/userfiles/file/60612020534.pdfIn PDF document text
    • http://dietaltop.com/userfiles/files/5873468755.pdfIn PDF document text
    • https://tinnituskozpont.hu/files/39133375254.pdfIn PDF document text
    • http://www.pethouse.es/ckfinder/userfiles/files/44135288244.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161443a27c289e---28749657986.pdfIn PDF document text
    • http://agecarekorea.com/ckupload/files/budubikamovuv.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/geserotev.pdfIn PDF document text
    • https://cremyco.com/app/webroot/docs/file/repobejuzoxuxisijetuwe.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/42533309115.pdfIn PDF document text
    • http://benhvienlaptop.biz/userfiles/file/katixibusefavofelabidir.pdfIn PDF document text
    • http://bbbo.handyfriendship.com/upload/files/levenave.pdfIn PDF document text
    • http://liburnia.pl/userfiles/file/48151146020.pdfIn PDF document text
    • http://cnkls.com/userfiles/file/1631615889.pdfIn PDF document text
    • http://protectakoteasia.com/ckfinder/userfiles/files/28253188475.pdfIn PDF document text
    • https://pezenasenchantee.fr/userfiles/file/12387359876.pdfIn PDF document text
    • https://telewebmarketing.com/FCKeditor/file/tidopalufalodelefed.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/2poa1f564j1d69n2sbcl2jpjud/jirumefinopevofolamu.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_off0000d0d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D1 10724 bytes
SHA-256: 6cbb62ea1bec2d12b4029ea620b2599a16dbd9999f6e489fba04b7eadb622f69
font_01_sfnt_off0000e96a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE96A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001017c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1017C 17564 bytes
SHA-256: 2692fab36cc1a23955d72e34fc0640006981ba46e4f662ccf8ff69037d068a07