Malicious PDF — malware analysis report

Static analysis result for SHA-256 b51bb4f77d5ced84…

MALICIOUS

PDF

69.2 KB Created: 2021-10-04 03:32:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3e1b40e67a894e3a7cbe7a18fd9b419f SHA-1: ec9b97011cd61b71e2fcaf044f844f965bed28ac SHA-256: b51bb4f77d5ced84dbaa876b302efa9bab4b155f3bd1027a0d0167d8205c8066
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF document identified by ClamAV as Pdf.Phishing.Trojan. It contains a link farm pointing to multiple domains, many of which are hosted on compromised WordPress sites or disposable hosting, suggesting an attempt to distribute malicious content or phish users. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://laborke.ru/uplcv?utm_term=the+elements+of+one+act+play PDF link annotation
    • http://ciatic.saintelserver.com/archivos_editor/file/8909392831.pdfIn PDF document text
    • http://lejuriste.ru/files/file/98846500576.pdfIn PDF document text
    • https://sieuthimaycafe.vn/uploads/file/42012290251.pdfIn PDF document text
    • http://vietcem.vn/public/default/ckeditor/files/41262633622.pdfIn PDF document text
    • http://angelofthewinds.org/ckfinder/userfiles/files/65796044217.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/u95vjt16nvkc05ft0bht43ssid/14717907748.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/dmac1i6kgqoq0crrp3nf48n099/27821920158.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/c9f178ecdcc7e97f97aa8ee29f8f5286/vosomadavupiva.pdfIn PDF document text
    • http://studioaeditecne.it/userfiles/file/kiwofeju.pdfIn PDF document text
    • http://immopolignano.lu/images/difupavepopedebafim.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/supakupoxiluna.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/5000d8f1315885eef82c21c8f99e3f80/45788800131.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/16156c46de68f3---79754031895.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/wujek.pdfIn PDF document text
    • https://beruanglucu.com/contents/files/wibijabuwizukaxurekevi.pdfIn PDF document text
    • http://pilatesmystyle.com/userfiles/files/zevanixunamojuber.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-15/20210915231253115641.pdfIn PDF document text
    • http://tuvanthanhlapcongty.biz/upload/ck/files/23867510179.pdfIn PDF document text
    • https://strategieb2b.com/userfiles/file/bojotajipekapuzit.pdfIn PDF document text
    • https://hv2barrier.com/application/third_party/ckfinder/userfiles/files/fuwufepoxeten.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161524e46e996b---42118989528.pdfIn PDF document text
    • 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_off0000ae48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE48 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c65a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC65A 16084 bytes
SHA-256: 4ff09cdbeb8a66ae31e42d9ce401e578679f4b05a6fa4f38e2ff4a318f15dcf6
font_02_sfnt_off0000ef34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF34 10632 bytes
SHA-256: 6f46ddddcdca199bd5fab761687b21be9ab46d7b7264fd751d68d87f0f453990