Malicious PDF — malware analysis report

Static analysis result for SHA-256 685a8f571e28c2a8…

MALICIOUS

PDF

86.8 KB Created: 2021-06-30 09:54:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 821d5755048dc95d7a3f9359ef38dfa8 SHA-1: ec694c5d5c8bb7a935c032eed790d5c97b0c3111 SHA-256: 685a8f571e28c2a8dcfc87fb70d7542585b28bd8c55d235fe928b91b7e0dd682
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites that appear to be compromised WordPress installations, serving as a link farm. Heuristics indicate this is a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/2454b2b8562639c9a43a5f2035708bb0/93368626444.pdf In PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3076e3feb1dade1fd428bb4b0dd6428a/45986970517.pdfIn PDF document text
    • https://voyagerf.ru/wp-content/plugins/super-forms/uploads/php/files/9cd56cb8bf06db13a378b06246a854af/jutafem.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/tkd1hpmo1kadj030qc2i5tr2nj/balewozexewuzo.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/59340543812.pdfIn PDF document text
    • https://bibliothequedesarts.ch/ckfinder/userfiles/files/97458635690.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4538d81004---wipuvuwavavetiko.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/44701123829.pdfIn PDF document text
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/67365487676.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606d15f94563b---vopimigunojufawarevo.pdfIn PDF document text
    • http://loveperfectionschool.com/upload/file/vigumosofuzowobuxowu.pdfIn PDF document text
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/g340grruvjmvmuk5n6f5dd9crh/30781322282.pdfIn PDF document text
    • http://jcpingie.be/public/files/kiradupugiwosobuzurufedim.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b6cee2549---pasupijejojoditava.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/0fa62e15009fa580763558e279990815/ridexipelabakuzus.pdfIn PDF document text
    • http://chocoenglish.com/_UploadFile/Images/file/16987497456.pdfIn PDF document text
    • http://asude.istanbul/ck_images/files/duwiwunexov.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/baa692fb5fcdd4b4d623853798bef1c6/welusemiti.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160abb23a73339---gawonu.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/43d9a07628af816c88e695ad0c88db46/zunademi.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d9060740a---98428655320.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/4fa61fd5544016c232f4fdf8b5304660/32224336720.pdfIn PDF document text
    • http://xn----8sbxab3abskk3a2j.xn--p1ai/media/file/1353428428.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=wow+alliance+classic+leveling+guidePDF 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_off0000efac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFAC 10592 bytes
SHA-256: 1b82bbf473e77a26c0501a2b520e33eb36ae51fbdc002114c3b662299681c602
font_01_sfnt_off000107cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107CC 17760 bytes
SHA-256: c45557ce68418f3d89b5b59bdca04ba9ba7efb8b51232c7b0ae194c62e3e7fde
font_02_sfnt_off000135b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1