Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5bbfb1116424c3b…

MALICIOUS

PDF

99.6 KB Created: 2021-09-04 04:33:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3d1ae274451c38beb7bc45ba1e67507b SHA-1: d04bf4881a131d299a18bb3097730611406b301d SHA-256: b5bbfb1116424c3baa3c0d12724c88e7a7b592dc0fc37102293f9d3650270062
96 Risk Score

Malware Insights

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

The ML classifier strongly indicated maliciousness, and multiple heuristics identified the PDF as a link farm. The document contains numerous external URIs pointing to various websites, some hosted on compromised CMS platforms. These links likely serve to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://crewmak.ru/uplcv?utm_term=diplomov%C3%A1+pr%C3%A1ce+pdf+uhk PDF link annotation
    • http://americansemitruckparts.com/d/files/gafav.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e31da6f79f---tatojumif.pdfIn PDF document text
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/71f74d2f551a18169699d71a8f8f6e68/gozametemevu.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612dfd87d4e51---gipajetunibamexagolufovup.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ca9a67a8c0---87796834857.pdfIn PDF document text
    • https://colegiumaniucarei.ro/ckfinder/userfiles/files/zosomasividofivivusojul.pdfIn PDF document text
    • https://ewt.cz/res/file/8446433488.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/dhjjuqb2qha62ieumuucdv6ua8/31797703106.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/pudimuxawis.pdfIn PDF document text
    • http://vuoncotichdep.com/upload/files/32330644547.pdfIn PDF document text
    • http://billsky.ee/files/file/79603858176.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c757c8dc254---rasiri.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/94f69159880d70e9429612ec35f70219/76639171439.pdfIn PDF document text
    • https://cortopolis.ar/userfiles/file/xujokavuzelok.pdfIn PDF document text
    • http://stpatricksreunion.com/clients/84553/File/xopafunikufodif.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a377dce7e5a---wotovizakebewe.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/xoluxudozegelagegemefitad.pdfIn PDF document text
    • http://lbhs1965.com/clients/6/6b/6bdd8f708684a1f547efbf97e1630fe5/File/lejosed.pdfIn PDF document text
    • https://loctra.net/userfiles/file/44228162695.pdfIn PDF document text
    • http://www.netcorp.hu/data/editorfile/24918652591.pdfIn PDF document text
    • http://galgalesh.com/userfiles/file/24254497246.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/olirozudemulet.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_off00011c69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001347b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1347B 20616 bytes
SHA-256: 1efcfe5c5b30acff024f0723a3645da54824706d678c92a486c900280295a980
font_02_sfnt_off000165f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x165F1 10792 bytes
SHA-256: 498e07c38784cfe5d5c3c7d8c99110b84b0ab73b91732c685320d0ceba199285