Malicious PDF — malware analysis report

Static analysis result for SHA-256 52db6b6dab6895bc…

MALICIOUS

PDF

74.4 KB Created: 2021-09-12 08:28:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e2a4324e03b46d7f73f37abaa88c1834 SHA-1: 3bf5755b9343820d8f4672bfb0b6c01217ffe36b SHA-256: 52db6b6dab6895bcdc16e44449416199fa6c60ad9a893c1fae4df386a0e11111
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The file contains numerous external URIs and links pointing to compromised WordPress sites and disposable hosting, suggesting it functions as a link farm to distribute phishing content or malware. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=android+11+q PDF link annotation
    • https://turismopontevedra.com/ckfinder/userfiles/files/1004974244.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161344b8649cd6---56376105178.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161306e469a74b---gilasubidokonadinajep.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613752a3434b6---19091566111.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613caba87cf08---30775312125.pdfIn PDF document text
    • http://kool-house.com/upload/editor/file/54579681529.pdfIn PDF document text
    • https://singhaniabrothersltd.com/ckeditor/ckfinder/userfiles/files/27098162613.pdfIn PDF document text
    • http://gostinica-domodedovo.ru/files/16132299445.pdfIn PDF document text
    • http://ipea.kr/userData/board/file/vazijexetudonisofarizaxol.pdfIn PDF document text
    • http://cdio.vn/uploads/userfiles/file/xijonakoxewiwigogu.pdfIn PDF document text
    • https://homeuu.biz/upload/ckeditor/pages/files/94862923440.pdfIn PDF document text
    • https://sunrise-photon.com/upfiles/editor/files/74343754580.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/d1bripqi0nfh5sm4dp2jjnkar6/85304232142.pdfIn PDF document text
    • http://zatexpress.com/upload/userfiles/files/dewexota.pdfIn PDF document text
    • http://taiwan-tsai.com/upload/files/zewotomawapub.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/57799523560.pdfIn PDF document text
    • http://daphongthuyhueminh.com/uploads/image/files/papawebiwijatowijevale.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9008662d22aeb39109063ab16a0c2e7e/19832901848.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3069ba37d---ganewe.pdfIn PDF document text
    • http://gyliver.ru/files/files/17006891251.pdfIn PDF document text
    • https://irrisyst.eu/files/file/52774325536.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_off0000c1c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d9d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D4 17684 bytes
SHA-256: 0888a8d812a3eaba460ca7a7c40b84051a84cf5642bdbabcd5dec6739f0e18d9
font_02_sfnt_off00010717.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10717 9816 bytes
SHA-256: c6532fb5972f23be664e581930bae219da1f48ed598889452574d920d59331f4