Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5c3fc6cc6c11349…

MALICIOUS

PDF

80.8 KB Created: 2021-09-07 19:12:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-22
MD5: a56deb09366037e4752c27c3335339af SHA-1: 6f16b0bf8dbaf0ba93c7711b729f8bf80f59fc78 SHA-256: d5c3fc6cc6c1134970d5bf930a3f2e3959db8ed20fd9876bc015bc0d00a93f1d
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • 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://wsp.pl/userfiles/file/28429137694.pdf In PDF document text
    • http://gmart-express.com/demo/uploadpic/file/94120886373.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/a011e6c43e744ce5cada8e646b7d1290/10503061332.pdfIn PDF document text
    • https://cplastik.com/data/cms/file/sonuw.pdfIn PDF document text
    • https://welltowork.org/wp-content/plugins/super-forms/uploads/php/files/7a2f965dc4181b43685d99b7724fafb1/88592849441.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f87b953d17---36757093706.pdfIn PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/timawokunisixav.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b734eb87438---fogudezanejegoleji.pdfIn PDF document text
    • https://totounited.com/contents/files/153588362.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/zozomodetetidofikosapa.pdfIn PDF document text
    • https://gym-rectif.fr/ckfinder/userfiles/files/solaxijodutozixexizi.pdfIn PDF document text
    • http://cinebuzz.be/uploads/userfiles/files/zujarazilagose.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b1b06b5a7f3---xogixejagisofeviberibeg.pdfIn PDF document text
    • http://saktigroup.in/uploads/xeserimigupod.pdfIn PDF document text
    • http://thessalonikiflights.com/files/files/67089136494.pdfIn PDF document text
    • https://abe-rdc.com/userfiles/file/19026851643.pdfIn PDF document text
    • http://wellfoto.cz/pictures/files/vimimifazerabixipupumure.pdfIn PDF document text
    • http://planao.com/ckfinder/userfiles/files/73518183670.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/moxamujazek.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/b60b72ae6ae6a4e4418d80a773cfb72e/zoluwevizibufu.pdfIn PDF document text
    • https://ntct-dz.com/ckfinder/userfiles/files/47172870938.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608319b3e8789---33132708220.pdfIn PDF document text
    • http://ugrctrani.it/userfiles/files/jigopibez.pdfIn PDF document text
    • https://adikkeempat.com/contents//files/84690907123.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=venture+capital+private+equity+and+the+financing+of+entrepreneurship+pdfPDF 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_off0000d4fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED10 17480 bytes
SHA-256: 3330a7345316391fa0a27286b092cd8b1e03bad20de0d9c7fc743ea0fce0d351
font_02_sfnt_off00011abe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ABE 11296 bytes
SHA-256: 1f12a97fae435320679305fa3012abed8f4f33a59dae23d8681af305d9cb1141