Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bc4c623b0423e07…

MALICIOUS

PDF

87.1 KB Created: 2021-09-02 01:04:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 564b8a234f5c198ef1afee0e60a90bdb SHA-1: 408bc9a39857e01b84414c2652533365ec96c6ea SHA-256: 9bc4c623b0423e078678692cdabcd2472c2a09f2d7ec6ac3412201774baeb59d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites and other disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are sufficient to infer a malicious attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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 https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/dausthlhf3vvucqvtls462lqfc/5952687364.pdf In PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16083960b3e885---78081537306.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b00ca7ac3f5---pipewi.pdfIn PDF document text
    • http://cokhihoangvinh.com/uploads/userfiles/file/turawebekawepuluwa.pdfIn PDF document text
    • http://nct-vn.com/userfiles/file/nixirurufokonadozun.pdfIn PDF document text
    • http://schuetzenfest-hemeringen.de/ablage/userfiles/files/97869853081.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/suxumepemasidetovoded.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16086b7b4cab2a---12544980003.pdfIn PDF document text
    • http://eros-arena-reutlingen.de/eros/userfiles/file/noginaxek.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/0354866920df230c45603347071e1c5b/jagulif.pdfIn PDF document text
    • https://codecs.ro/images/file/12550523162.pdfIn PDF document text
    • https://yasacompany.com/upload/files/xokavegazol.pdfIn PDF document text
    • http://rrrc.us/userfiles/file/20140396889.pdfIn PDF document text
    • https://mebelihome.ru/upload_picture/70873118316.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/didizigikudadokidet.pdfIn PDF document text
    • https://ascend.sut.ac.th/ce/2017/src/plugins/ckfinder/userfiles/files/fevulit.pdfIn PDF document text
    • https://mosconi.net/userfiles/file/fijuxetipikojuxuvadafagu.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/bezagawanenij.pdfIn PDF document text
    • https://jokerprod.net/userfiles/file/98701333447.pdfIn PDF document text
    • https://insolite.lu/img/userfiles/files/5003592438.pdfIn PDF document text
    • http://studio70.eu/userfiles/files/potomeweponegiluk.pdfIn PDF document text
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/9ccef2586a61cb69a5434c869bac4d3b/vavusolukumipoxuxipexud.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfd3b7c1a84---39639804459.pdfIn PDF document text
    • https://truck-diagnostic.ru/wp-content/plugins/super-forms/uploads/php/files/e35fed4662c4142688bbcbf6caa4d660/41907157025.pdfIn PDF document text
    • http://vietxetai.com/wp-content/plugins/super-forms/uploads/php/files/e08t1gba3su4f6toa52ijp90uo/tifafezamakitaguwojo.pdfIn PDF document text
    • http://pokewaveanaheim.com/uploads/files/61149009518.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=how+do+i+ask+about+salary+in+an+interviewPDF 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_off0000ee50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE50 10828 bytes
SHA-256: e4c18895eb759a1118bc1f7a7a77257bdf55d3794562f8ab5533df5324180b1f
font_01_sfnt_off00010773.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10773 17616 bytes
SHA-256: 9cfedade2dea43c337b84924d53edce979052ec5f72d0f6d4fc4be69e2ddf7e3
font_02_sfnt_off0001353c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1353C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1