Malicious PDF — malware analysis report

Static analysis result for SHA-256 5109b3749234b65c…

MALICIOUS

PDF

70.9 KB Created: 2021-09-28 05:50:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 90470856a5e58312168128dca764963c SHA-1: 8962235d32f4cfd6f7ff65ef378bf0f97ac79661 SHA-256: 5109b3749234b65ca1bbecbb3cac73c266efe9ad49d7f0dc0443e0fe4bcabfdf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The presence of embedded URLs and the nature of the heuristics suggest this PDF is designed to facilitate phishing or distribute further malware, likely through the linked sites.

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 http://bajkolandia-leszno.pl/userfiles/file/97927514393.pdf In PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/aecf1176813e34bbf297cd626e2f8484/tesekigetojavidapedunufib.pdfIn PDF document text
    • https://ichibaninfotech.com/ckfinder/userfiles/files/wuzobibiki.pdfIn PDF document text
    • https://artinterior.bg/userfiles/file/59537006259.pdfIn PDF document text
    • https://kaktutzhit.by/uploads/files/67634638325.pdfIn PDF document text
    • http://tznjl.com/userfiles/files/gobulasalofururaxa.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/duzimubizuravukex.pdfIn PDF document text
    • https://crossfitbeeshark.ro/app/webroot/files/userfiles/files/rivud.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/5e665bea58bac91a1183ff629d952511/7547535269.pdfIn PDF document text
    • http://remont-m.com/userfiles/file/11011796012.pdfIn PDF document text
    • http://rinsacars.com/files/others/nuxomewidiregebaju.pdfIn PDF document text
    • http://elitacasa.it/images/file/99595684045.pdfIn PDF document text
    • http://nieruchomosciklodzko.pl/files/file/6552136510.pdfIn PDF document text
    • http://bancodevida.com/bancodevida/admin/images/image/file/75020291545.pdfIn PDF document text
    • http://grafichesirio.com/userfiles/files/muxozafixite.pdfIn PDF document text
    • http://ooexperience.be/assets/Image/files/rivejalevup.pdfIn PDF document text
    • https://meganimal.pt/site/upload/file/lopetakupekafinew.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/16141bae88716f---5141278162.pdfIn PDF document text
    • http://uleshuzatshop.hu/files/file/1163367659.pdfIn PDF document text
    • http://lscapital.it/images/file/26582712562.pdfIn PDF document text
    • http://feminella.ro/upload/fck/dobukibodunefifutine.pdfIn PDF document text
    • http://sgadsahodayatarntaran.org/sahodyatarntarannew/userfiles/file/42517236470.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/161516a5834aea---49036687451.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1614b9ddd27c3c---23252650325.pdfIn PDF document text
    • http://cachnhietwin.com/luutru/files/wewixurofowu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=uninstall+app+on+my+phonePDF 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_off0000b50c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB50C 10536 bytes
SHA-256: 0639798c6d59c506942a59f84a4fc83e340fa8cab57c0dfdef7e764de72dac28
font_01_sfnt_off0000cce1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCE1 15996 bytes
SHA-256: 3b4e89f6e5af14f02049626ae6ecd771723b17e19cd55f51abcd8eda27dfceb9
font_02_sfnt_off0000f55e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF55E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1