Malicious PDF — malware analysis report

Static analysis result for SHA-256 13ae1b24a3229891…

MALICIOUS

PDF

89.5 KB Created: 2021-07-02 05:36:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: de4eb4213c1a96c4e556f9757f5c2407 SHA-1: 26ab37783b25bd7125f89151120afd7226b63daa SHA-256: 13ae1b24a3229891a7c03adb6b9c36cd9a1387eccc634fce48a7af300b053636
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a malicious PDF detected by ClamAV as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to compromised WordPress sites. The ML classifier also strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the PDF structure and link farm behavior suggest an attempt to redirect users to malicious content, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7d6b8fbc2---nokekiwabidu.pdf In PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/641t2o4o49kui8f7vsjpsak7ob/xofivodibuj.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160caaf9949ee6---zamodoluzesiv.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/7ac603273bcd74b9be0236259079e8df/51869353553.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa66e615eb1---31075921171.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/dpfpikq95o0jgaq18ehmudphc4/kanofarebupa.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/f1ff5785945209de3d2b328beacea221/sibotugikevozuj.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/8qbskbk4lq47kk6iimqmjaus62/81002811253.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b39f7b2e312---patusoferutorefizu.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/13b1d96bfbc9d56587ede346d7105cbb/24414003179.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/zijufubixujasadegi.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b144d97f8fc---pagumaz.pdfIn PDF document text
    • https://thehero88vip.com/ckfinder/images_store/files/jabotubufedexetojegi.pdfIn PDF document text
    • http://coyada.com/up_images/up_images/75803719028.pdfIn PDF document text
    • http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077b6ec63723---35081891819.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d42dac6ca98---rurikimekabobu.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160737bff815d7---gorowowonijasedomifu.pdfIn PDF document text
    • https://rebel-guitars.com/wp-content/plugins/super-forms/uploads/php/files/d4d95549fa003b76e99458440ed58bc9/29975227711.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609855e9d9051---pabixubokubagabeva.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb81fb7b5e---zukukumewetukosewedasi.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ffc8596475---63398549292.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=how+many+calories+are+there+in+a+glass+of+winePDF 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_off0000f9c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C3 10972 bytes
SHA-256: 978d10b8be2a64d5ab720b1d29ac8bf4171f77fb0e3944ba31e6686ecaac0956
font_01_sfnt_off00011319.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11319 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012b2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B2B 18008 bytes
SHA-256: 21653f2afd18f741d69c5008d9ab25d3cf2fe0fc8842271e07c946ef15954b63