Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb12f6d5041d34db…

MALICIOUS

PDF

71.9 KB Created: 2021-09-15 22:48:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f47652e9cffe91196f53d41d3d927990 SHA-1: 2d0882a6ec69b628ea4ee25bc0af0b518aa35baa SHA-256: fb12f6d5041d34dbe9bf987801c3fa12cf225613931d8abff828ccddaaa4ac92
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a malicious document, potentially leveraging embedded JavaScript for exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://infrive.ru/uplcv?utm_term=weather+radar+pro+apk+free+download
    • http://smepil.com/ckeditor/userfiles/files/tasuduwumalotutifemi.pdf
    • http://fisioterapiasuzzara.it/userfiles/files/jibajivivapolofa.pdf
    • https://samsunyapi.com/userfiles/files/newevosomilufilum.pdf
    • http://perfekt-dom.pl/designhome/admin/userfiles/file/jibogodegerar.pdf
    • http://flyingwedge.com/uploads/assets/file/tojexupuzar.pdf
    • https://pmms-online.com/assets/file/48915415338.pdf
    • http://tce.vn/imagesflashupload/file/vepomasemepaxesonorinekod.pdf
    • https://garnet-medical.com/userfiles/files/41089363011.pdf
    • http://cocoon-source-harmonie.fr/public/file/43451519966.pdf
    • http://lakshimi-kaatsu.com/user_data/packages/default/imgfiles/66261298699.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/3f3ac8d28af54ee993a990852ed8da5b/nozopidarumesimepoduwu.pdf
    • http://cu-mbc.com/ckfinder/userfiles/files/58706339014.pdf
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/migudutozolelom.pdf
    • https://rentcar888.com/uploads/files/202109110213204423.pdf
    • http://nagyberki.hu/sites/default/files/fck_uploads/file/55793297901.pdf
    • https://aronabritcan.com/userfiles/file/kiguxubifebesuzorenewivop.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/kic2viscc5jp771ppbhj9lpd70/ledugujotuvuxilugozadugi.pdf
    • http://21cedu.com/pds/userfiles/files/nixapuzodaj.pdf
    • http://phaptangpgvn.net/app/webroot/upload/files/17417001415.pdf
    • https://mimpishio2bet.net/contents/files/nunamuwunamumipuderuxareg.pdf
    • http://studiomuraca.eu/userfiles/files/kewogujatewizeg.pdf
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16138bfb314524---91722554201.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613b812171f42---rituworinip.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b786.bin
0c9b75908c8f03b6522a52f37d64a8e435f771af8e1943896e24095d720a1954
pdf-font-stream PDF embedded font (sfnt) at offset 0xB786 10508 bytes
font_01_sfnt_off0000cf6e.bin
b2e62d61e7e4b6eddb1006282304f59aa21db2eb63dbd4080319760c78e1ee4e
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF6E 16616 bytes
font_02_sfnt_off0000fa48.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA48 16792 bytes