Malicious PDF — malware analysis report

Static analysis result for SHA-256 088a3566c4d2fbd3…

MALICIOUS

PDF

80.4 KB Created: 2021-09-07 05:07:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1af1970a41ff053160d3b8d6cc972fb1 SHA-1: d292354e5203444f8e765cce3617849f7fab08c8 SHA-256: 088a3566c4d2fbd3dce6c84afae066d45806350a6f68061bec81e28f34b2c1cb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised websites and disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the presence of embedded URLs and the overall structure point towards a phishing or malware distribution scheme, likely initiated via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://coretry.ru/uplcv?utm_term=formal+written+method+of+short+division+worksheets PDF link annotation
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/2p7772oq3rlu142c7q9f16mbj0/4276767016.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/bokipokevazebawetiluteke.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160862bbd0c630---7795586279.pdfIn PDF document text
    • https://emotionalgift.com/ckfinder/userfiles/files/8077439300.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/aa9b3874c6ba07d8b43fd4ff71d46715/76171524555.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/047b6292f0cf747e0cec67ee8955e0fc/26061552883.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/vusakexadiruzuri.pdfIn PDF document text
    • http://gma.ge/admin/ckeditor/ckfinder/userfiles/files/43403244160.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2f47d2826e---42736038298.pdfIn PDF document text
    • http://kelvista.lt/images/files/moneja.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c91affd0f7d---dawamadilutisorufu.pdfIn PDF document text
    • http://indecomavo.pl/inc/xerajupuguboxa.pdfIn PDF document text
    • http://mobiliteit.nu/files/jazukuvi.pdfIn PDF document text
    • http://kimsanghun.com/upload/userfiles/file/2021821037433875.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/0bt3cnkh5vhpvr7h4feo684rgi/13549972976.pdfIn PDF document text
    • http://www.ufolep-69.com/contenus/files/sukolujokowu.pdfIn PDF document text
    • http://www.lnk-creation.fr/upload/file/gafadamixutomugelo.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611c7765e8e2b---deloborepelologulutibo.pdfIn PDF document text
    • http://prograsifkalip.com/files/71076957744.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/05823d393f87748d6a2cad0f0a83c4d2/53120560098.pdfIn PDF document text
    • http://ecole.ru/text/images/file/41198953772.pdfIn PDF document text
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609594bece5cb---tobefuzikagun.pdfIn PDF document text
    • https://aashianarealty.com/file/vumalasitofudoxumewe.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/6835801321.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_off0000d5e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E1 17432 bytes
SHA-256: bdeb047fc055d6c6215fbab4c8b841422e507174008164cb34cc7fb83cd21373
font_01_sfnt_off0001028a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1028A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011aa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AA1 10840 bytes
SHA-256: 651c8e7c2d20953c273430bdf8b1fb71386b3bf626d5f1270cd7dcb9325f4ff5