Malicious PDF — malware analysis report

Static analysis result for SHA-256 dba82d81da760d8c…

MALICIOUS

PDF

95.9 KB Created: 2021-07-23 20:12:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 25a21b250dc29f4b307ac6b5b00e3491 SHA-1: 488a84f92ba2e3c7cdd5ac17e72493e05987d0bc SHA-256: dba82d81da760d8c636a9fbaba499fab706251d41a3ea65dbb63717d873a2946
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm, with many URLs pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with attempts to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/897a3e47a2a07796e4695702aa1e5920/31078251032.pdf In PDF document text
    • http://eurekaelearning.com/upload/news/file/65009258298.pdfIn PDF document text
    • https://jurad.eu/files/file/75724055153.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a43ede59801---61325771810.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/xemone.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c59c4ccaaff---xulubexirudusazapoporuful.pdfIn PDF document text
    • https://666666.vn/upload/fck/file/wemujetujisibamufi.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160e71951d39f0---bomesebuludatamivevuke.pdfIn PDF document text
    • http://matkinhantai.com/luutru/files/nokalanemuvudiwegafamiw.pdfIn PDF document text
    • http://msamerica.net/clients/873634/File/gejomuvu.pdfIn PDF document text
    • http://minhanh.com/files/lifoworifarigaduvimof.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b209c4540---91588394156.pdfIn PDF document text
    • http://tai-yang.tw/taiyang/upload/file/49431096380.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf80c95674a---laravoxutubunomosepet.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160961f135aafc---81672514358.pdfIn PDF document text
    • http://cloverpark1960.com/clients/1/17/17c242f0968dc4bce059666b43fbd075/File/78517379100.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c74fa01b44---sinuzefekewiwodisupaforu.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/76613994909.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/b6e9a92eda7147ed70cf5e39bb4b0d7e/tademugasilexafeb.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6e71bbd16---levitivesixobinotoxivaf.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608800a335351---fewunewigugu.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083d6789410e---pirerabezuwaxokebagijobob.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1aecda2c2---93741051231.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16076263433cc0---68798214269.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/50343553252.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=java+2d+game+programming+tutorial+pdfPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6b3a2519e5---76756171439.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_off00010f88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001279f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1279F 10948 bytes
SHA-256: 0b48ba2cccfeba2c3b5dd9b35cce7ec3671a30423381122e35c29d499ba0634c
font_02_sfnt_off000140d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140D0 18488 bytes
SHA-256: 5ab392349756f17c20fb874c449eb51442f628dff78e5c26a18922dc1dd8f364