Malicious PDF — malware analysis report

Static analysis result for SHA-256 36fd97a48929ccff…

MALICIOUS

PDF

83.5 KB Created: 2021-07-04 02:22:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a4fcb1f30d349c03743d9cfb3efd5e0f SHA-1: 5a64daa0d620011d44552944a742cb39c39c3ed3 SHA-256: 36fd97a48929ccff37b86ed1d9ee447fd5f175a8df6f896b676a7d02eee1346d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file acts as a link farm, pointing to multiple compromised WordPress sites that host further PDF files, suggesting a distribution mechanism for phishing or malware. The presence of external URIs and link farms on potentially compromised infrastructure are key indicators of this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/d63282046e9bb365a9735b52381b709e/sazage.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/fevf666eal3cauhiutorrtn4oo/87870462818.pdf
    • https://rubin2000-distribuitorshop.ro/userfiles/file/1295869438.pdf
    • http://change4best.ru/upload/file/gujizamejujelizulolidoxiv.pdf
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/6c2c8e849b65583aad5285f61ed3798c/wokopamo.pdf
    • http://cdmatik.com/uploads/file/fejosibotexon.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/337cad06dd16108473638aaa651a1ba4/sifagubirekokuvaj.pdf
    • http://vipforiraq.com/userfiles/files/wunezovozowilejasafiza.pdf
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1608e63502e3d5---posedodanunol.pdf
    • https://majubesar.info/contents//files/sugutixifoj.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d803fc459ef---fagudirawin.pdf
    • http://theheavent.com/userfiles/files/54422515349.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072cd4617ae4---letolozuliga.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ef2ac54865---3628562387.pdf
    • https://eberli-medical-supply.ch/upload/file/nawafexewiveravivu.pdf
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/20b75fb6660420309a699693ecac9778/88737857073.pdf
    • https://artasedanasingaraja.com/uploadfck/file/83546899265.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/ba3qo9621e18936863j5cs863k/nepuvejigebizigurisaju.pdf
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bc6860afcf1---98720811604.pdf
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/9d9013e47f442d9f8dfd0a6c76a5e1d1/79468000164.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c8644592308---xifuvikivabilipeda.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=the+battle+of+labyrinth
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e44f.bin
0642b7d18f542b49340f7f6623edfd5f2e179faeb20fd4ea45286c5f1deb5ddc
pdf-font-stream PDF embedded font (sfnt) at offset 0xE44F 17368 bytes
font_01_sfnt_off000111d2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x111D2 16792 bytes
font_02_sfnt_off000129e9.bin
e08658ae001b760d8a83d8d15fd193faf46e83e147e0256325c6b3ca7a36b7c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x129E9 10360 bytes