Malicious PDF — malware analysis report

Static analysis result for SHA-256 781bf2cdc19c975f…

MALICIOUS

PDF

92.6 KB Created: 2021-07-17 09:17:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: bbc7d1517b14ed7e682bb462e1472f61 SHA-1: be2e0aa7d13e561eef53e3068db7766f1512245c SHA-256: 781bf2cdc19c975fd161e8c0029666910177043a7fe8c47650e275182f2bb6e3
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to compromised WordPress sites, suggesting it functions as a link farm for SEO manipulation or to host malicious content. ClamAV detection and ML classification strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://timnhanhonline.net/upload/files/96913585712.pdf In PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/nibiruratoxevuwixewigav.pdfIn PDF document text
    • https://genia-groupe.fr/images/files/mafes.pdfIn PDF document text
    • https://aterhesseg.com/up_image/file/jutakagili.pdfIn PDF document text
    • http://wisewood50th.com/clients/3/35/35ca2b70ae131fa39667c240906a3fe4/File/salubogofasanukujefug.pdfIn PDF document text
    • http://gilendor.cz/userfiles/file/noganapanejaporikeganarel.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/8d86277804e8e8182975ccd3f5cd8592/48487749261.pdfIn PDF document text
    • http://suachuaspa.com/upload/images-content/files/zunifewupunowe.pdfIn PDF document text
    • http://tai-yang.tw/taiyang/upload/file/tegukubapu.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/3d8e929b1ae658744b8f6533d50ffe60/87578181594.pdfIn PDF document text
    • http://staceyasp.com/UserFiles/file/pogelubetajuxipugavaror.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607430d0e0d9f---wasasewoniromuranimonenir.pdfIn PDF document text
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/28a33d1c68f013aecab7a8989febb553/sibuwa.pdfIn PDF document text
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/27929913461.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f576a79dec---newet.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099af4f28284---7042871320.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16095f998967fb---patixukalorikararixon.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210604220738_zpi8l3.pdfIn PDF document text
    • https://bodwellassociates.com/wp-content/plugins/super-forms/uploads/php/files/3b65986de0fed710943eb96445d2a98b/70487394355.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/bft4gcspi5sg70mk1q360pjm5p/65875076143.pdfIn PDF document text
    • https://jordanadams.com/ckfinder/userfiles/files/25091901594.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f53f29bc9f---31651211100.pdfIn PDF document text
    • https://torgradio.ru/new/files/file/53425685965.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=colposcopy+and+cone+biopsyPDF 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_off00010a17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A17 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012229.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12229 16652 bytes
SHA-256: 7bc80f0f7116389bc54cf41bc664cf8f24852d503daae85eac94f53bf103a57f
font_02_sfnt_off00014d66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D66 10592 bytes
SHA-256: b27575600d8b5d88140d78b7c8b45ad087d4fb87e31b80c30fdb1449abb49d77