Malicious PDF — malware analysis report

Static analysis result for SHA-256 571d082346dc145f…

MALICIOUS

PDF

72.3 KB Created: 2021-09-14 08:35:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c0083602b2a1449a58d78360573cb392 SHA-1: 3455ce410028f105cbda1976ea001fb4301abd25 SHA-256: 571d082346dc145fa2358ed882c4afb2c7c44098466b9851e4991f8d47222285
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to disposable hosting or compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crewmak.ru/uplcv?utm_term=the+walking+dead+mobile+apk
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/49083989513.pdf
    • http://sdhmladavozice.cz/userfiles/file/84685927774.pdf
    • http://alphasigmaoverseas.com/userfiles/file/xevofukokuvumaxidawin.pdf
    • http://101balkon.ru/upload/files/zekutosomanutijilesobop.pdf
    • http://jumpstart.mobi/ckfinder/userfiles/files/janojomexaxadulena.pdf
    • https://lmbri.com/WYSIWYGImage/file/16135198222.pdf
    • http://notariocprietoa.com/notaria/documentos/files/1108502956.pdf
    • http://www.sushmitamukherjee.com/fckimages/file/9458885993.pdf
    • https://hkfew.org.hk/ckfinder/userfiles/files/xejelawakopevur.pdf
    • http://e68momo.com/shopadmin/upload/files/kevasirajotuvisajema.pdf
    • http://wecans.net/_UploadFile/Images/file/138865227.pdf
    • http://abpjse.news-read.com/upload/files/tamabibixezijor.pdf
    • http://master-stroi76.ru/userfiles/file/vikusipu.pdf
    • https://afma.pt/site/upload/file/24173400387.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613edd20240f4---zugisamijasezotox.pdf
    • http://debeight.net/UserFiles/File/75761951462.pdf
    • http://chiangmai-esc.net/user_img/files/47130818461.pdf
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/76f095ba682c896ba824a79c41b99bd2/getesujawasotowiwafanuxe.pdf
    • https://lotusmarinevn.com/upload/files/nurolafejipawekamov.pdf
    • http://redondoclassicburger.com/uploads/files/dedixizugekarotofufad.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/cbed57f0059a17e6356fc171bdcd4100/35609778700.pdf
    • https://thietkeweblongan.com/upload/files/moxulile.pdf
    • https://hilanguage-com-tw.triangle-design.com/files/mefalinukiko.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/cf7432d1e6fd0a085764b331ecab365b/91695751577.pdf
    • http://coolbiotech.com/upload/files/robosimebaravotasu.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_off0000b7af.bin
8d80ef83475874856e21f11a421375c0fa86206263f4954c156f3c3c558d1d9b
pdf-font-stream PDF embedded font (sfnt) at offset 0xB7AF 10752 bytes
font_01_sfnt_off0000cfbe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCFBE 16792 bytes
font_02_sfnt_off0000e7d0.bin
61171b8ff35cd1e5ff11fb7784bc3e263c2f29a09bb02a3d691512c1200d6055
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D0 16884 bytes