Malicious PDF — malware analysis report

Static analysis result for SHA-256 c517fccc0570d03b…

MALICIOUS

PDF

74.9 KB Created: 2021-09-18 01:36:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: bc97187eb1f05e0d5f630a8a7774f7b9 SHA-1: 909a2592608377af973eb989bf8cba4c2d230424 SHA-256: c517fccc0570d03b3f5e5c7dfe9365db5386329b6cb50d5d2f8efc985196fd84
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple disposable or compromised domains, including a compromised WordPress upload. The presence of numerous external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest an attempt to distribute malicious content or phish credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://av-jet.ru/userfiles/file/zebetazeputeruwejugiguz.pdf In PDF document text
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/111528344589.pdfIn PDF document text
    • http://computerdoki.hu/user/file/zisezixolurut.pdfIn PDF document text
    • http://imobiliariaimperio.com/files/files/90768224104.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021091402595998.pdfIn PDF document text
    • http://miass.realxenon.ru/uploads/files/29099052431.pdfIn PDF document text
    • https://francoisdaulte.com/ckfinder/userfiles/files/vivixewekosow.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161363d041fb3c---38840809053.pdfIn PDF document text
    • http://gonganmi.com/userfiles/file/sewefodikejukerewozaje.pdfIn PDF document text
    • http://avvolodin.ru/upload/file/lasekulikagabodavodadadi.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16132c27d0752f---39835988340.pdfIn PDF document text
    • https://kaptenhoki.net/contents/files/94230751021.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613c974fd51d3---wixale.pdfIn PDF document text
    • http://primebrokeragetx.com/ckfinder/userfiles/files/96183289202.pdfIn PDF document text
    • http://loca-granderoue-montaletang.com/ckfinder/userfiles/files/dalurowid.pdfIn PDF document text
    • https://b7b.reviewz.eu/app/webroot/files/userfiles/files/22942597833.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/burejewenagenad.pdfIn PDF document text
    • https://lifeteacher.tw/uploads/files/202109170036107060.pdfIn PDF document text
    • https://bepxuyenviet.com/upload/files/30250625284.pdfIn PDF document text
    • http://mptech.vn/ckfinder/userfiles/files/dutakixagunujog.pdfIn PDF document text
    • https://svingenieria.cl/userfiles/file/sinaxesizikegafol.pdfIn PDF document text
    • https://gymlesgeants.com/upload/editor/file/95502796185.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/k51s4h2on5hbhagg6kk0nktm3r/gotulujevuxosibakadowexiz.pdfIn PDF document text
    • https://nepalihemp.com/ckfinder/userfiles/files/89622439333.pdfIn PDF document text
    • https://mikludava.lt/images/files/xumoluw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+cast+iphone+to+android+tvPDF 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_off0000c269.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC269 10708 bytes
SHA-256: f232e590aab3cb629f8a6f578ed3f4dddcdaa70fe30c9758bd019e0b9b13d27d
font_01_sfnt_off0000daf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF8 17028 bytes
SHA-256: 6cd55af6c9744e78154f2362ad2a0e3acc6cc8eceec9f5240f2a6ad139ec01c8
font_02_sfnt_off00010638.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10638 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1