Malicious PDF — malware analysis report

Static analysis result for SHA-256 876b4bd233a358da…

MALICIOUS

PDF

70.3 KB Created: 2021-10-03 22:25:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e66a5fb1230acf2c0b9ab93894d0fbc1 SHA-1: 41e5fa594c75d92b071efc74b11ff0b60efd29ae SHA-256: 876b4bd233a358dae425faa3b03d890bfbb771a936d957d2ecc0dc3baae8f6dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous external links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution campaign. The presence of embedded URLs and the nature of the heuristics indicate an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 https://irlanc.ru/uplcv?utm_term=tvd+and+harry+potter+crossover PDF link annotation
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d722f58b5c---32816269369.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b8d344ed91---61797379948.pdfIn PDF document text
    • https://go2germany.ru/files/file/84223099036.pdfIn PDF document text
    • https://arerp.kr/data/file///60698676063.pdfIn PDF document text
    • https://elsadaulte.com/ckfinder/userfiles/files/92325403151.pdfIn PDF document text
    • https://rocha.pt/userfiles/file/kewafobejo.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/53203089349.pdfIn PDF document text
    • http://trubaopt.ru/content/file/jugozim.pdfIn PDF document text
    • https://duongthuy.net/userfiles/file/61064194854.pdfIn PDF document text
    • http://qataminational.com/uploaded_files/userfiles/files/lotop.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/vodawasuxerarorutatazag.pdfIn PDF document text
    • http://wawa757.com/uploads/files/memuzogexatorekowifub.pdfIn PDF document text
    • http://retrolondontees.com/userfiles/file/2954017924.pdfIn PDF document text
    • http://silver.jo/ckfinder/blanc/files/42255425254.pdfIn PDF document text
    • http://abpaluso.com/upload/file/kiwupavuzitoluriv.pdfIn PDF document text
    • http://globalone-mould.com/gbw/fckfiles/20210912084839.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/ih5v4iffgfm4hcl09dls37te7u/79193782424.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161559bf6c1a76---wodazevefuraniza.pdfIn PDF document text
    • http://sudeoksa.net/userfiles/file/20210901115753.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/16132d0c92ba8b---lewog.pdfIn PDF document text
    • http://gfzgt.ch/upload/file/gagafifebewofenajelesaz.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_off0000b202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB202 10616 bytes
SHA-256: 5c0fea64d07de1b510607f4dc5e440f410fc47d816811e69ee78e0abfd4d2e9b
font_01_sfnt_off0000ca43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA43 16268 bytes
SHA-256: 0ddf90823530334098e06efab7b9e6ab84fa21d5a5341e413108bde6983d7aa2
font_02_sfnt_off0000f365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF365 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1