Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e0db78f81cb7a12…

MALICIOUS

PDF

69.3 KB Created: 2021-09-13 07:20:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 96d4ae81ca8d20b2f33bd870cf9c5213 SHA-1: 03fff165e2d46d810f5fe8d5ed62d517d0bf7252 SHA-256: 4e0db78f81cb7a12ac251aea36877523cddc2151cc12029eb515f37b8a685bae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which point to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection or further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://huntic.ru/uplcv?utm_term=ceh+v11+lab+manual+pdf
    • http://bioident.pl/photos_fck/file/mokup.pdf
    • http://grappin-annat-como.com/userfiles/grappin-annat-como.com/file/lawamelofuso.pdf
    • http://kibbkw.com/uploads/files/niwatijesod.pdf
    • https://icon-studios.com/userfiles/file/xagijaluwisowokimukenezej.pdf
    • https://tims.ro/ckfinder/userfiles/files/dememolubuzelo.pdf
    • https://ostrichpharmaceuticals.com/userfiles/file/2807632651.pdf
    • https://sieuviet.net/webroot/img/files/31331111814.pdf
    • http://coverybox.box8websites.com/ckfinder/userfiles/files/38586717098.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac6f479fdf---674591879.pdf
    • https://euforbiabulgaria.com/uploads/pages/files/kaguwigemuvowezutud.pdf
    • http://munsusa.org/userfiles/file/20210912054936.pdf
    • http://cp-1.ru/userfiles/files/52391292987.pdf
    • http://king-tableware.com/uploads/files/202109130254548258.pdf
    • http://jayeonrak.com/upfile_editor/2021/files/13054802656.pdf
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/04d569ae5beb54f788cddfb4b12f0eec/fokugemigalegojuvewikag.pdf
    • http://chatyzvule.cz/uploads/82082578831.pdf
    • http://orderkiwicafe.com/uploads/files/tutusogidejusesojog.pdf
    • http://goddesshair.net/upload/users/files/wizijavurura.pdf
    • http://xinxinhouseware.com/uploadfile/files/4580199788.pdf
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/d3cdfb86a91e66d5d07c8b000bf76e19/josixodifelijemidoxet.pdf
    • http://blueleaves.ru/userfiles/file/zigap.pdf
    • http://www.oteliapelsin.ru/ckfinder/userfiles/files/18946763779.pdf
    • https://groupburuemas2.com/contents/files/degofugo.pdf
    • http://modra-skola.cz/userfiles/file/falalulipojumajadizeginev.pdf
    • http://2sisaccount.com/userfiles/files/76478226543.pdf
    • http://ytovietnam.net/ckfinder/userfiles/files/40713426873.pdf
    • https://betenagro.com/sites/default/files/file/jewidatir.pdf
    • http://crossfit28.com.s125853.gridserver.com/siteuploads/editorimg/file/kizojarigilorivizefokim.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b359.bin
767c1ac6f06e4d3e7d70786329c843c2031216ee907aacb9be8592d66abf697b
pdf-font-stream PDF embedded font (sfnt) at offset 0xB359 14460 bytes
font_01_sfnt_off0000d793.bin
53c09e93ecab21586cf4b9efbbdc4c0f4382c9c62a0127c3f34ef0c682de0f76
pdf-font-stream PDF embedded font (sfnt) at offset 0xD793 10576 bytes
font_02_sfnt_off0000ef5b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF5B 16792 bytes