Malicious PDF — malware analysis report

Static analysis result for SHA-256 a42c5ea2130be29d…

MALICIOUS

PDF

83.4 KB Created: 2021-07-02 21:55:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 2e3152edf69618d5580062261f2b7099 SHA-1: 38ba8a30535e42d6ef4a0add45ca6b968ebe1f1b SHA-256: a42c5ea2130be29d4080ad764e1dac9ea6a4e629e8dc8110aa41c84a94a34442
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is a PDF identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The presence of PDF-specific heuristics related to compromised CMS uploads and link farms further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://daeryuhealthcare.com/ckupload/files/xudofemanux.pdf In PDF document text
    • https://aduanaldelvalle.com/userfiles/file/75097416103.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d2d882b24c1---gudav.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/39b43aff7b4fe7ea39d1622d1f25e833/vuxogamiwiwotinilolifunip.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080031bc90fe---11505503067.pdfIn PDF document text
    • http://emeat.ru/var/files/34400134036.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/16095211fa88f6---vitoteralidexosukamovesi.pdfIn PDF document text
    • http://cathayred-csr.com/img-cathay/files/melebinejemifosirifozevaj.pdfIn PDF document text
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/64101642d79403ad2399cbe79350a0db/tefobosalezanaveruwevat.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/f2543a243b689fe177aa9aec3d8d53d5/98427006314.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/pawetumularuwogupet.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab19c92a63a---50989911481.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf6c1009c9---70983640799.pdfIn PDF document text
    • http://yuha.be/_files/file/wixowojavalotifoboxerek.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/1qsvqgdsf4kc8r8tvrdtc2jdeb/duxolebi.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160714d99d4419---gamamuj.pdfIn PDF document text
    • https://sunrise-photon.com/upfiles/editor/files/pirupunewunagudet.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/7k52kgc2ctn75f3g8qm6iehoh8/54724218397.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/41458101237.pdfIn PDF document text
    • https://artbynela.com/uploads/file/fuvilut.pdfIn PDF document text
    • https://mauspro.net/upload/files/zafomejujarevik.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16099e910d99c5---kamulebadetijub.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083b411300d6---gorupanevogasenebepe.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c47bf553c9a---sawuvomiwanevadipetik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=good+morning+happy+sunday+images+hd+free+downloadPDF 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_off0000e43e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE43E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC55 11188 bytes
SHA-256: 3173854ce1e69da302e8a2eb999fe07c659070af649a22832ab91a91388da331
font_02_sfnt_off00011626.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11626 16252 bytes
SHA-256: 3961ead7576d5d9867e330a1b2c1e1adc9e001a9a658e739394a0e2ffa3732d5