Malicious PDF — malware analysis report

Static analysis result for SHA-256 3770e467b10c45b0…

MALICIOUS

PDF

97.2 KB Created: 2021-07-07 04:17:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3c80ff087397e6779cc2ef9dde6ffd70 SHA-1: ae47a8cddb138a34f81ec665fe0a798c8f946420 SHA-256: 3770e467b10c45b020073e797d1083497c7d7d303b597633a7c087e5012c2237
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites utilizing the Formcraft plugin for file uploads. The ML classifier strongly indicates maliciousness, and the structure suggests a link farm for SEO manipulation or to distribute further malicious content. No scripts were extracted, but the overall pattern of hosting potentially malicious PDFs on compromised sites is a common distribution method.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5ac527b968---13098936673.pdf In PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b9d33ccd6---venelowajoku.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160a0420d5f972---37655741599.pdfIn PDF document text
    • http://bhs-class1957.com/clients/35434/File/riritibobapumigo.pdfIn PDF document text
    • http://moto-trend.cz/public/files/fck/file/xozuwitizivivokabinidi.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160df4eb55b2f0---99094971092.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/ucghlo28opdsebsga1tuo793r2/77921076869.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607fbc61d690b---xikudasijugike.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/55lm0pq2h1qhsfgan97vm7b0uc/85292953650.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083d3f8dd641---bonovoxepoguzetetun.pdfIn PDF document text
    • https://mvpartners.be/images/uploadedimages/file/gobuwibatadujazirujigivu.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bfa2362f53---78608984138.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/fe45247bce6b0caed4a44fae4264d4a2/benetaxix.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/c7879bf562871e3428d6e43767409f86/zewimazajiratesebarabulan.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607df4713ce46---8409176541.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/mokizipaputekab.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/10822466081.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/a1c865f635d9a37837de496744d0ddac/duvukudidadi.pdfIn PDF document text
    • https://w4gw.com/file/toneb.pdfIn PDF document text
    • http://morgancountyoh.com/userimages/45646719570.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/b31fc4872db72f384f7dcaaaa6898545/16463984137.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/lokegu.pdfIn PDF document text
    • http://tillmanfamilyreunion.com/clients/b/b7/b7385abc5988d1ee605fea7695e3d00e/File/jejaboxogemaxuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=types+of+drilling+fluids+pdfPDF 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_off00011ab2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000132c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132C9 10592 bytes
SHA-256: bc17f8808bf336e184c8a541154b3618d72c1cbf9a2e3bea767df91fa54f7042
font_02_sfnt_off00014ad3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14AD3 17068 bytes
SHA-256: 5191e53e2d9a9081d85bace0d8cf8ef60e473140e7ac02ad87ddc7c4f2be514a