Malicious PDF — malware analysis report

Static analysis result for SHA-256 33d338bb25793a6d…

MALICIOUS

PDF

72.4 KB Created: 2021-09-02 17:09:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 604535a23b25dba4e47ba419e9d57be3 SHA-1: 395d451a08e500815a2f52a471c598e3595d39dc SHA-256: 33d338bb25793a6d5e07dc93d4f3b45c3d188509f280fffac5b7cae806bca502
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous links, many pointing to compromised CMS upload directories, suggesting it functions as a link farm to distribute malicious content or phish users. The presence of multiple external URIs and link farm indicators points towards an attempt to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/29c0a1762acfc0409580534ed14843b1/wurujefo.pdf In PDF document text
    • https://www.alapan.org/fckimages/file/jakotijinosuduneduwon.pdfIn PDF document text
    • https://goooinggroup.com/userfiles/files/20210803_080825.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/gavadegi.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b85fd696851---vikunojadegutavuzof.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/pajemexelipuxitufufev.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/fufeb.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/2efad5f1813ea9563837fff53c8be6ef/fezufiset.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/0f2c8228bedf97f8d84052d4d8957bc5/12045379029.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/82u1ts4bpe04uo3mfnj3a59tdt/24965127202.pdfIn PDF document text
    • http://laduses.nl/image/file/wunusedukiduwo.pdfIn PDF document text
    • http://horizonpestservices.com/userfile/nenejuza.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160bcea90b90b0---rasipufogeliwezi.pdfIn PDF document text
    • https://couvreur-hautdoubs.fr/internet_new/images_et_fichiers//file/vuzilubewaluwa.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b5f8f87c213816045f4b1efdb37e1564/20043691279.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c90d5b5be7b---dadugosin.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4673c15e5---72250245260.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608223cea536e---damaxa.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160832be2836c7---62737299447.pdfIn PDF document text
    • http://solee56.com/ckfinder/userfiles/files/josagamagem.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160b4b42cd9f68---nifofenijukid.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160f5a715033e6---ronatumalisinufaben.pdfIn PDF document text
    • https://hzautomatisering.nl/userfiles/file/tipoxunajenoxigofapevizo.pdfIn PDF document text
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vomisetemuxumonexile.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=etica+para+amador+fernando+savater+libro+pdfPDF 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_off0000b71e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB71E 17348 bytes
SHA-256: da48305777b64ae29c306ce471ca917d221016bb7d687d209d6a78966a19dc21
font_01_sfnt_off0000e2bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fad6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAD6 10968 bytes
SHA-256: 5328f7fbfd4fc69bc3f0c75f3dd68d66f485c29ccedf73a9a35c929638d642a9