Malicious PDF — malware analysis report

Static analysis result for SHA-256 41d83d07efdd9f86…

MALICIOUS

PDF

108.2 KB Created: 2021-07-23 03:51:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f5453cfd3ec707123256872d486f041b SHA-1: 14c4e94e058690d410b97fa576bfaf4c33638a98 SHA-256: 41d83d07efdd9f868355584b2bf61434feae8c8f748f52f03eafe909a5b2da60
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a phishing or malicious redirection attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are consistent with a link farm used for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://klasykarozrywki.pl/public/images/fck/file/49659020912.pdf In PDF document text
    • http://hagelkonzept.com/userfiles/file/38133475778.pdfIn PDF document text
    • http://kingcraftviet.com/uploads/ckfinder/files/razunikaxuguloxir.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/63725566868.pdfIn PDF document text
    • http://gvs-russia.ru/admin/ckfinder/userfiles/files/roguxezuwuriwuwufope.pdfIn PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/63336569670.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/9ie4rmmkrqk8tt4j2b3dk7gdj2/84425202303.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607207658a1e1---tebubifosinib.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbff30c145a---76014190455.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/n25uic5en6aqqod6cupu9t8mne/36726676012.pdfIn PDF document text
    • http://jakebenmd.com/clients/0/0e/0eef9d569b11303d075d19626cc6f958/File/bidebomemowupetamemaf.pdfIn PDF document text
    • https://teamcode.net/upload/files/28063672798.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/j8j4s5mlum750ug0tsvsenmcs4/33173098836.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/70428b329ba9bed765e94f4a1469f6c0/tosujovujole.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/aba4c6c4f49d401b9b23ee2fd6433703/2946495283.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/4164deddaf0ff6e22cb74867357d6a44/nuvuk.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d944c87cb3---56977268423.pdfIn PDF document text
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/474f5e4d713ef4aed4f10fe5478e2a78/sakis.pdfIn PDF document text
    • https://planet-pvc.com/upload/files/mojidakumonureri.pdfIn PDF document text
    • http://dalnoboy.net/data/filestorage/upload/files/lasovizomujesab.pdfIn PDF document text
    • http://posekatzahradu.cz/files/file/14909008883.pdfIn PDF document text
    • http://jadever.vn/Images_upload/files/1299775750.pdfIn PDF document text
    • http://dichvutot99.com/webroot/img/files/6639194178.pdfIn PDF document text
    • http://sonnenheizungen.ch/fckeditor/editor/images/file/xuwanebuzakamimi.pdfIn PDF document text
    • http://xn--b1agaa2anfqdp.xn--p1ai/ckfinder/userfiles/files/31591168967.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=words+with+twoPDF 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_off000143ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00015be0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15BE0 9980 bytes
SHA-256: cd82b7d7660ae3a4296e4e03f01bae389dc775cb28ff22a58ef259f9970776da
font_02_sfnt_off00017221.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17221 18384 bytes
SHA-256: 8ba74514a3b14ad899372bef5d950645705639257fa445ebb9f8018d1cb73574