Malicious PDF — malware analysis report

Static analysis result for SHA-256 3356c75cd5d947ee…

MALICIOUS

PDF

78.2 KB Created: 2021-08-30 10:15:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 7da6f0320c628f9de1c743ba7d23a3e1 SHA-1: fb0c47af32e5ff80a59a243e246806eeaf41bb11 SHA-256: 3356c75cd5d947ee55d5160037519026fd6d7d002fb70935324dff31db331cb8
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to manipulate search engine results or distribute further malicious content. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 5

  • 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://huntic.ru/uplcv?utm_term=american+micro+bully+price PDF link annotation
    • http://baggiez.net/userfiles/file/nibinitesowukidakojizi.pdfIn PDF document text
    • http://kopdesign.nl/userfiles/file/31694567072.pdfIn PDF document text
    • http://canoeing.by/pics/files/gobetekusekoxiluzibidedef.pdfIn PDF document text
    • http://patroha.hu/file/raxumegelasagogutidexi.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a571379d3c---27248433069.pdfIn PDF document text
    • https://securityguardsupply.org/php/uploads/file/vugeterenev.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/871f20882325cb4b843f25e98c0b3d37/66924560696.pdfIn PDF document text
    • http://bkm-market.net/userfiles/file/femukafibamijipijiwevomaf.pdfIn PDF document text
    • http://www.edgartownschool.org/uploads/files/wexinufenowivef.pdfIn PDF document text
    • http://headrepublic.pl/images/files/81810872133.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160c4a7a873a92---balajabudafebigowa.pdfIn PDF document text
    • http://cphs1970.net/clients/877309/File/tojuzabumanibomutekiro.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wuvaf.pdfIn PDF document text
    • http://hophungvietnam.com/app/webroot/uploads/files/32917386436.pdfIn PDF document text
    • https://renetravel.ro/images/files/purixavir.pdfIn PDF document text
    • https://mm-podium.ro/userfiles/file/76813316633.pdfIn PDF document text
    • http://mmprogetti.it/userfiles/files/gedexuv.pdfIn PDF document text
    • http://nhac.ditimchanly.org/Images_upload/files/19923929585.pdfIn PDF document text
    • http://careerdynamic.com/clients/3/3d/3d9dba0a3645e5854abf1db7654b9c86/File/jowiv.pdfIn PDF document text
    • https://inprovitbrasil.com/ckfinder/userfiles/files/kofifomeguxenepikurex.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/4ba86036c99a4a4cf901051fd4e968f2/girizovawod.pdfIn PDF document text
    • https://telenovella-bg.com/files/76947560.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071a80af068e---pefozaxijarar.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/ad14eb272a5b419e0e48bc8091aa9a13/89488216055.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608befda748ad---26707519341.pdfIn PDF document text
    • http://mountcalvary76.com/clients/9/90/9062e1c9f2360b2cedac6e2854879500/File/4360431027.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_off0000cd30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD30 10604 bytes
SHA-256: b66fd85d6ab683ea762e522dd6da54f11821d41d882d1010a2255673a4362c50
font_01_sfnt_off0000e520.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE520 18236 bytes
SHA-256: 848caf6c4eef82ea0253f0cd2f01826551b8ed9ccf893864593a51a740ce4822
font_02_sfnt_off00011368.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11368 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1