Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4cbd3f39391bc14…

MALICIOUS

PDF

86.5 KB Created: 2021-09-02 15:00:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 84e5b8d856b7a0b843324f73f6c28039 SHA-1: 0106587c1729e2c4e71daa91b553571e30d0957a SHA-256: e4cbd3f39391bc14975d2f63acbedc9a1c74d32748d7a43725fb60c9323ea162
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites hosting PDF files. This behavior is indicative of a link farm used to distribute malicious content or redirect users to phishing sites. ClamAV detection and ML classification further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f5bc0bc97---bovivavifu.pdf In PDF document text
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/iq82792p7f1mccn5domp3dio38/fexuxupuvefililex.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607042a91123d---gagifalulivawi.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/231c4e993f55f487f575a7f240a18cc8/pibewibixales.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7f1edf0a5---54320035117.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/ad993568fb4238f98935ef641dfe8a19/xoxaxixumod.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b441be841d1---wegamituvujatanilukisoxa.pdfIn PDF document text
    • https://promise-land.com/upload/file/siturije.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/winodevekekadujepatokaw.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/e77f40257465413d14655a66974efd84/90608771080.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/l19d2h1p1n31353b0bh5p2spcs/kugizuziresiropodexuw.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a7abc9192fe---pakigukatekixakiko.pdfIn PDF document text
    • http://cowmoo.org/ckfinder/userfiles/files/27701255787.pdfIn PDF document text
    • http://global-insurance-broker.de/downloads/dikesuwajigunimuwuw.pdfIn PDF document text
    • http://jlm-kg.com/uploads/file/runosumo.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210727_050914.pdfIn PDF document text
    • https://wildarium.com/ckfinder/userfiles/files/fewulowavejuteko.pdfIn PDF document text
    • http://gld-lining.com/user_img/files/zugifojivirikegafumuxitix.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b21fec8e551---mizojumipipevubon.pdfIn PDF document text
    • http://adacu.org/userfiles/file/20210821013109.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/be10acbc6391ee634487a6ac60d26423/24981753560.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a2a6b6b9e---32873729976.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/49be036844689391edbe65892d5880a6/44210043094.pdfIn PDF document text
    • http://hzdsbg.com/uploadfile/1621103349.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160af679f04da1---wusefopigivopimomusuku.pdfIn PDF document text
    • http://lblussana.it/images/file/fadixijerozaperamu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=buscadores+academicos+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_off0000ec89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC89 18668 bytes
SHA-256: b7e958c8d2c4d1b9264a497111d866a33c8210824df1cffe1bf9c2ef10aa34d4
font_01_sfnt_off00011bac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BAC 10684 bytes
SHA-256: 01be59b7033ce16916d7050979b423c085fb44403983a1d7970ae98e27345f5a
font_02_sfnt_off0001343a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1343A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1