Malicious PDF — malware analysis report

Static analysis result for SHA-256 87a71c7e21f97038…

MALICIOUS

PDF

89.1 KB Created: 2021-09-17 16:16:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4a45fbdf1c0ce1f1c2aa49a882dbdeea SHA-1: a07e2ea2239d12d5bc3f7c191167438571dfe003 SHA-256: 87a71c7e21f97038dce4bb35a04439d74c6cade2142bfc1f4faa12f567e1a657
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://synerhu.ru/uplcv?utm_term=mardaani+1+full+movie+watch+online
    • https://quatden.vn/webroot/img/files/tesovonu.pdf
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f13e017b47---92395282988.pdf
    • https://sanruouvang.net/images/uploaded/file/sodotidiweva.pdf
    • https://ccskin.com/geektic/files/26030777742.pdf
    • http://alhouti.com/userfiles/file/57829503435.pdf
    • https://armenia4d.com/contents/files/sutukizepet.pdf
    • http://gopherandsquirrelcontrol.com/admin/images/file/bapukawofosejul.pdf
    • http://kommunikator.nu/demo/userfiles/file///falowizevebamerudolase.pdf
    • http://njuhome.pl/ckfinder/userfiles/files/mijigetifuvufujaduwab.pdf
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/91cqb4rjjbcl7v70k51ag73fbm/xusavumiwifuwajo.pdf
    • https://sicurezzaips.it/uploads/file/wesununipofomadovade.pdf
    • https://esz.jp/img/editor/files/65595833342.pdf
    • https://rugerwafers.com/demo/ruger/beta/userfiles/files/18882868390.pdf
    • http://kodemari.info/data/files/jejegaxeved.pdf
    • http://ggmtc.net/userfiles/files/xupubinebulorajedo.pdf
    • https://teamcode.net/upload/files/11834985131.pdf
    • http://wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/84330787668.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/16141d86b466aa---1721513001.pdf
    • https://rusepress.com/uploads/wysiwyg/files/dutolokimasedes.pdf
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/a47844cafedfb54d08e6c86cb1ac319b/6229115763.pdf
    • https://shioturboapi4-xyz.com/contents/files/64954829801.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/rt2s7fbc58ocdflu1m306evkcf/latewusisamuveta.pdf
    • https://soosekszer.hu/upload/files/52300891710.pdf
    • https://liantoong.com/archive/upload/files/fuwefelefivutefokifewisi.pdf
    • https://fsbulletsandbrass.com/userfiles/files/41159110470.pdf
    • https://pezenasenchantee.fr/userfiles/file/lerokeliwijofodudu.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_off0000f866.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF866 16792 bytes
font_01_sfnt_off0001107d.bin
7cb2a7de515b999a65765d78b10fda346c092fbe9d1086d250b46fe36589ece3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1107D 10872 bytes
font_02_sfnt_off00012973.bin
d09f5ad70f9ac5ce5fa8c1ce8ce1c232aebd08adcf1d656d2ebcf60f472394d2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12973 17732 bytes