Malicious PDF — malware analysis report

Static analysis result for SHA-256 13ebd1bd5b3dd584…

MALICIOUS

PDF

82.5 KB Created: 2021-10-17 05:49:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4bdea943896d2c91c236c95dcb3fdf97 SHA-1: 6d81a862fd3b7a06976473c597e2f0faa4c427c8 SHA-256: 13ebd1bd5b3dd584904a38c30418ea68074b9fd7ba487fd7699bc363e99f2869
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues about its intent beyond what the heuristics suggest.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/79687cb5f3bfc85cb33f67341611150b/miveto.pdf In PDF document text
    • https://tongdaidoanhnghiep.com/app/webroot/upload/files/86373320420.pdfIn PDF document text
    • http://sfalojistik.com/userfiles/file/gipukiriwu.pdfIn PDF document text
    • http://gemtown88.com/PicOther/file/94630721735.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615667e72fac0---3344558081.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/judotugerudevi.pdfIn PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/nelogolijaka.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/f79ba2b757a55e7816d8efe412f846fa/paxem.pdfIn PDF document text
    • http://le-nora.com/userfiles/file/dexovefetazokumide.pdfIn PDF document text
    • http://www.tempshift.com/app/webroot/files/uploadimagesfile/48517134834.pdfIn PDF document text
    • https://coopinproject.eu/ckfinder/userfiles/files/1281815296.pdfIn PDF document text
    • http://seamacros.com/upload/file/musazikozo.pdfIn PDF document text
    • http://comitatoamiantovelodromo.org/userfiles/file/jolozafububivoxunaso.pdfIn PDF document text
    • https://wanfutemple.urwaydesign.com/data/file/userfiles/files/12378497598.pdfIn PDF document text
    • http://bonezi.morefriendship.com/upload/files/64887435965.pdfIn PDF document text
    • http://basse-normandie.annuaire-regional.com/ckfinder/userfiles/files/38818639069.pdfIn PDF document text
    • http://ttmm.co.jp/ckfinder/userfiles/files/femutumegojuwanevinikev.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1616b5074a4cea---zapemukapitisusapowila.pdfIn PDF document text
    • http://skiflogistics.ru/userfiles/file/48661381779.pdfIn PDF document text
    • http://satisfytech.com/ck/upload/files/ninatijaxawuxufavasu.pdfIn PDF document text
    • http://gibisch.com/files/files/xogowinizowo.pdfIn PDF document text
    • https://nepalonetours.com/userfiles/files/65897753465.pdfIn PDF document text
    • https://paperland.bg/uploads/file/27236219109.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/tgwjJlsMqHc/uplcv?utm_term=say+for+instancePDF 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_off0000db77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB77 19528 bytes
SHA-256: aa27e2cca6f95768d06109ab2b81bafc0c2ed51a250afc0529067fe9e532094c
font_01_sfnt_off00010c7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C7A 10472 bytes
SHA-256: c6b8c147cfb348d0c0d0ecbc126dd08f5495b71b3788ad277f5257b244cda8be
font_02_sfnt_off0001246f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1246F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1