Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4623956518309ea…

MALICIOUS

PDF

91.0 KB Created: 2021-09-13 09:02:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 865d561f44db35aed7c0a553748b6d60 SHA-1: 42d75e7d24cc9940afd08cceb68f48af4b832453 SHA-256: d4623956518309ea8c1dc0b3467fd7da5cbf57ee54a21d1bd45aefde5e992db5
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to a variety of websites, many of which appear to be part of a link farm designed to obscure the ultimate destination. Several heuristics indicate that these links are hosted on compromised CMS platforms or disposable hosting, suggesting a malicious intent to distribute phishing content or malware. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://medvor.ru/uplcv?utm_term=smallest+richest+country+in+the+world PDF link annotation
    • http://vanharteyoga.nl/uploads/files/95877057703.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/zobin.pdfIn PDF document text
    • https://pmapmc.com/userfiles/image/files/81983743789.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/3155485103.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/88850974518.pdfIn PDF document text
    • http://jingyitech.com/uploadfile/52373005615.pdfIn PDF document text
    • http://chinahongji.com/d/files/70516365224.pdfIn PDF document text
    • https://gyn-koe70.de/obrazky/file/vumipabimakunenam.pdfIn PDF document text
    • https://darshanam.com/ckfinder/userfiles/files/gidazidositawesodizat.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/6b33393ff8e17512bd5db41efeacdc8e/tagogutisiji.pdfIn PDF document text
    • http://huh.hu/UserFiles/File/23528315661.pdfIn PDF document text
    • http://okuninka-biale.pl/userfiles/file/177830711.pdfIn PDF document text
    • http://chip-chup.hu/upload/file/70635625452.pdfIn PDF document text
    • https://reformedgeneration.com/userfiles/file/nurebu.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/ea9ec82b5755b8d2ae40d7e9881cd8b2/nukafiremogexo.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/sanetutaxilopitoziz.pdfIn PDF document text
    • https://dermatologie-chamonix.com/userfiles/file/gibominigirubotimor.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16132285e15f59---11406271501.pdfIn PDF document text
    • http://alpha-cp.com/userfiles/file/92104699323.pdfIn PDF document text
    • http://basumati.com/app/webroot/ckfinder/userfiles/files/seletubavorexofefoguru.pdfIn PDF document text
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/dopigusap.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16139355f83420---wezaxikimimiz.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/74950610940.pdfIn PDF document text
    • http://www.w.radeton.cz/ckfinder/userfiles/files/xeberibukanuxigeduxavu.pdfIn PDF document text
    • http://s250801404.onlinehome.fr/img/uploaded/file/farumifiwik.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_off0000fa9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA9F 11008 bytes
SHA-256: 1309a7c97e9179e22afd10f5237fcdd5f6a9ccb585cf7d7e22d6bf65a75888a6
font_01_sfnt_off00011411.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11411 18884 bytes
SHA-256: 2cb9ee9bad68cf40127e2002f5cb6704ed7e94d63b3a9305ad9aeb99e592ec8b
font_02_sfnt_off000145f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1