Malicious PDF — malware analysis report

Static analysis result for SHA-256 f640c9a5f9ea79fc…

MALICIOUS

PDF

90.0 KB Created: 2021-07-02 07:09:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 3e425395861094087192f1f246bb3ed6 SHA-1: 678cfc19e5213063bebc37aa08e45f1f67453ccd SHA-256: f640c9a5f9ea79fc7b7affa3c6655071ea505efcded98625e08b31e2be2f59fb
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, pointing to numerous compromised CMS upload locations and disposable hosting sites. These links likely lead to phishing pages or malware downloads, consistent with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/950422dc5cffc4ceeb6708d823b30f11/82124897172.pdf In PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/befdd28947951281c207d9d6649f8db3/dowisusexabu.pdfIn PDF document text
    • https://vestol.bg/files/file/gavepedewavig.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160af95510e564---fowowibakilajatukiwuza.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c8867682121---85780045251.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/2875e00f9a39be04f56896233c1e9c13/38268814455.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/bba7df81f611418ef0b2860df1e7cfb3/vilonivorigasategipokor.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a180d0eb41e---xikifulovinefusutevo.pdfIn PDF document text
    • https://service-panev.com/userfiles/loboritukudamesidapota.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c090ea1bc8d---suzurapexukeneleluwer.pdfIn PDF document text
    • https://imagebeaute.fr/userfiles/file/48851325697.pdfIn PDF document text
    • http://ck-tct.ru/userfiles/file/56652057367.pdfIn PDF document text
    • https://kopari.hu/files/file/kewukeponeseton.pdfIn PDF document text
    • https://biocoils.com/img/file/nagovogelonavir.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608097c68fd04---jobidevakegu.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608929a86bfae---warilotinisumuwivoraze.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/502f2be14aa70cdd82cb241f02eb7a90/gugotijegiponavopo.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/41967527837.pdfIn PDF document text
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b853e65b32e---jixutuwuguvegem.pdfPDF link annotation
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607419ffe874a---41188259326.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a0a01d3ec---paxuj.pdfIn PDF document text
    • https://ecoretras.com/file/67110567144.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/behq7b2lgngehnkg5kesu1jh47/jorujirekiv.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d04b3bb0cc---kuwaweki.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=famous+person+from+connecticutPDF 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_off0000fd02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD02 17604 bytes
SHA-256: bcc0f4c4c9340ab6a123a5cdfee3e7de937761e795bedf95609615ce57813559
font_01_sfnt_off00012a51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014268.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14268 10672 bytes
SHA-256: 668df0857b0d6dd268c8a2ef8dca6fc611bff14066c926f9c911297db861879d