Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1aff2eb72f59234…

MALICIOUS

PDF

93.7 KB Created: 2021-08-18 03:43:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ee94b0123e52170e840a3e29dad20133 SHA-1: c8c96ded401b6e54edd17bc567ed9dc3bc54acd4 SHA-256: b1aff2eb72f592343d05d7b7756d58c780b9fbb672f7dbc90d597fc7f179ceae
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDF files hosted on various domains, many of which appear to be compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through these linked documents. The structure suggests a link farm designed to obscure the ultimate destination or to manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://successstudio.net/userfiles/file/dukagobilokixozigunivina.pdf In PDF document text
    • http://hataylezzeti.com/resimler/files/gadomaxawefevuvokarod.pdfIn PDF document text
    • http://siamsankyo.com/Uploads/file/ruzutarokajipafigirunix.pdfIn PDF document text
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/dukekuzewepeninovaku.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160819bf64b876---4290430766.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16119ac0d81e87---40632048395.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160c96cb229c95---65478025375.pdfIn PDF document text
    • https://www.puskinas.lt/ckfinder/userfiles/files/sifiponumodawofoxonujepil.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/51777632839.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/16258069059.pdfIn PDF document text
    • http://shihtzufurbabies.net/clients/d/d3/d383cf0c90cf2d2391705d5438694b4c/File/97969536509.pdfIn PDF document text
    • http://hattingtoemrerogsnedker.dk/userfiles/file/6944059005.pdfIn PDF document text
    • http://rotarylaspalmas.orgdocumentos/file/67082197173.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/47756636044.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/ba51c7f9d6143b2ef486e4dca55b84b0/rivakepasatuma.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/tivugegak.pdfIn PDF document text
    • https://sentinels.ro/userfiles/file/33984635801.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/bb6109ab901cedeac2e594fe89567ab4/16421347977.pdfIn PDF document text
    • https://roofmed.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a18848f0b3c---51747952202.pdfIn PDF document text
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/4533438c4c31835c3059b467862b6a15/3289436065.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098eb48bdc71---68094132743.pdfIn PDF document text
    • http://www.pics4us.de/userfiles/file/pikitadi.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/jalevoxebozezum.pdfIn PDF document text
    • https://autohausnschmidt.de/userfiles/file/mosixuxin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=letter+from+birmingham+jail+questions+and+answers+quizletPDF 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_off0001058f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1058F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011da1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DA1 18016 bytes
SHA-256: a4c97849aa19dde2556af333db9d4638365d8feea1697620398659fda78f90ec
font_02_sfnt_off00014d24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D24 11420 bytes
SHA-256: c55810f89a7ec7a75f222ec67b7b0eef0fc24ecd0f15fa0ef1ca6d753839d187