Malicious PDF — malware analysis report

Static analysis result for SHA-256 a937e10947c8a2e9…

MALICIOUS

PDF

83.9 KB Created: 2021-09-12 00:07:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c506d0583dac56b3aae4c7afd2efa12c SHA-1: 3fa13846e0c258c0ab041afc5f263785613dc259 SHA-256: a937e10947c8a2e94e06f3bbde553068581aa27c6135897464a84f32a0d8a3ec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of link farms, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of external URI heuristics and link farm indicators further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://infrive.ru/uplcv?utm_term=ek+vivah+aisa+bhi+full+movie+123movies PDF link annotation
    • http://studiotecnicolari.it/userfiles/files/25319671248.pdfIn PDF document text
    • http://africalegal.nl/userfiles/file/94099513771.pdfIn PDF document text
    • https://gres-k.cat/userfiles/file/xizos.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/60382023131.pdfIn PDF document text
    • https://abriganature.centralcms.cloud/galeria/files/natejezidironarovoduze.pdfIn PDF document text
    • http://hotelrealerimini.it/userfiles/files/82370627193.pdfIn PDF document text
    • http://rudolphalexander.com/uploads/files/44327627318.pdfIn PDF document text
    • https://expobar.vn/app/webroot/files/images/pages/files/vovevaxebez.pdfIn PDF document text
    • https://leresto-niort.fr/images/userfiles/files/76533982870.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/nugokuz.pdfIn PDF document text
    • https://infotechloyalty.com/bot/ckfinder/uf/files/lamujifosavidibik.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613acad527717.pdfIn PDF document text
    • https://limsurempat.com/contents/files/27534737796.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/9h65ll341tv3s32njl29p1ul27/22276263396.pdfIn PDF document text
    • http://klm-co.ru/foto/ck/files/10170864472.pdfIn PDF document text
    • http://elencostruzioni.it/userfiles/files/solevudibefenus.pdfIn PDF document text
    • http://alburigiott.it/userfiles/files/sexijuzi.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/jerisibi.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d19428bec5---52354288974.pdfIn PDF document text
    • http://ibnuaffan.com/ckfinder/userfiles/files/16173892523.pdfIn PDF document text
    • http://vivaibonomo.it/userfiles/files/3792740683.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/fogoguminaxiduzikifogasav.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_off0000df4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4C 10900 bytes
SHA-256: f0d6f17f8139ca374c8d62b2817c20d5e84b6b835c1054971d2f0ceb729f8bb7
font_01_sfnt_off0000f8a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B4 19004 bytes
SHA-256: 161f13f2564925c9390dc3b80034b94c6d1e2a61cf1640c51ac7ed4feb6260cb