Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d3a20a8c9c1287b…

MALICIOUS

PDF

126.9 KB Created: 2021-09-02 22:55:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b91c5c4f3ffb6cba5b3c37fff5834e4c SHA-1: 79cca0370f577c4394f2f8b62df7b27157d9fe1a SHA-256: 1d3a20a8c9c1287b544f94a2fd9ee77ad6856bad5d4277fd0f546868cce046fa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or SEO abuse. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the heuristics confirm the presence of external links designed to redirect users.

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://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078dc0d077cb---vikusetorutomuxekole.pdf In PDF document text
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/dc014356bb39c1b701237be629e4f2d6/xemakosadivujugo.pdfIn PDF document text
    • https://lionkingbali.com/uploads/file/64752592027.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf7d48ea85f---tasumeridazasukubofavamug.pdfIn PDF document text
    • http://heryeryesil.com/resimlerfiles/zazivewodot.pdfIn PDF document text
    • http://xn--2-140-swe8h.xn--p1ai/files/talamoxatazu.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607a10c8a565d---14583462437.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160709aac5befc---42499574280.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608f7fa856456---wamisuginokogurunozopuk.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a97595c0eef---xuxesifijekod.pdfIn PDF document text
    • https://xn--80aanugxqi.xn--p1ai/admin/ckfinder/userfiles/files/radedozinowanosaf.pdfIn PDF document text
    • http://qqwandai.com/uploadfile/file/sufixi.pdfIn PDF document text
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/ropobujivuli.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/5098663538.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/bikowobuj.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/f22a0876606158bdc817823ddc4839a7/jaraworadefegetepe.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/34889376874.pdfIn PDF document text
    • http://jtour.vn/userfiles/file/45624970364.pdfIn PDF document text
    • http://cephedanismani.com/images/pages/file/89607066026.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/44775730896.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160be0dbc6a326---73801478330.pdfIn PDF document text
    • https://alshamiltrading.com/alshamilfiles/file/zexopefurilaviwadafuvudid.pdfIn PDF document text
    • http://ricarda-allegra.de/userfiles/file/weregamikexolusubetezika.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=dsssb+tgt+physical+education+syllabus+pdfPDF 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_off000180a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x180A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000198bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x198BD 11156 bytes
SHA-256: 9fa5101208cd75f8d4bf997b6c19f050c6e0ee1498367374dbb5b667038c032b
font_02_sfnt_off0001b262.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B262 22056 bytes
SHA-256: e9c5e0598bc0e8704a28f62e985b553770802f95b822cbda2cc12f325cbb2742