Malicious PDF — malware analysis report

Static analysis result for SHA-256 c91077b3e396488c…

MALICIOUS

PDF

90.8 KB Created: 2021-07-30 19:34:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 819af645421927b015b68e90ffcf2cae SHA-1: 66c378cf320b5c5b9256d5c947be61c3da85edd6 SHA-256: c91077b3e396488cf77b0b7d3ea57a7e1220f8251d73690794cd0c9811f8323b
156 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating it is a link farm, with many URLs pointing to compromised WordPress sites and disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

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 https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/e2931c87a1f7870a72ec43cfc10ce6e6/55656578896.pdf In PDF document text
    • http://alohatoypoodles.com/clients/1/11/1122824db0f83c9e74cf39311881f217/File/31101289177.pdfIn PDF document text
    • http://architettoletiziamasciotta.eu/userfiles/files/33505527000.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc9ae235979---vukidop.pdfIn PDF document text
    • https://craftsmancuttingdies.com/wp-content/plugins/super-forms/uploads/php/files/9fg59at65u9qjton6dlkmnemvs/24147821531.pdfIn PDF document text
    • http://circuitoinsulargc.com/documentos/file/90348389383.pdfIn PDF document text
    • http://atol-res.pl/uploads/file/tawivaxuvarejuga.pdfIn PDF document text
    • https://hyundainhapkhau.vn/upload/files/jurafovegili.pdfIn PDF document text
    • http://candientuvibra.com/images/file/bufakegabugefepofujixab.pdfIn PDF document text
    • http://meadclassof1991.com/clients/c/cc/cc689d7a74a098ef67b43942063c7ff9/File/japokatavosileroja.pdfIn PDF document text
    • https://tonymusic.se/UserFiles/files/5796858338.pdfIn PDF document text
    • http://mytmbc.org/fckimage/file/gumutozam.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160711fda1b6a1---biguxepefosano.pdfIn PDF document text
    • http://vogiantinhmach.com/media/ftp/file/gedejifolinikisisa.pdfIn PDF document text
    • https://mlmrockstars.com/ckfinder/userfiles/files/62186529751.pdfIn PDF document text
    • http://scandirent-new.ru/uploads/assets/file/vodobugodereweluwajaw.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/2qd6b1lc82g8uoo3tvt2timoet/luranupur.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/lisugerewifupadifuru.pdfIn PDF document text
    • http://kargo-box.com/uploads/files/voripezaw.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160806ada7625b---7274803822.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/e460e8a53351a53348d1ca96db09bce5/jezegagasazigodune.pdfIn PDF document text
    • http://phuongdonggolf.vn/app/webroot/uploads/files/nijuvubakawepo.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160abdcf57c4d8---92327586349.pdfIn PDF document text
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/f326e0c66e8b243b2575a0436d23b54a/luzoxufiduxafovigevi.pdfIn PDF document text
    • http://cuatudongsaigon.vn/uploads/files/3277693458.pdfIn PDF document text
    • http://harasim.cz/uploaded/files/85357675483.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=romoss+power+bank+20000mah+reviewPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f358.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF358 1760 bytes
SHA-256: 478d64aad58a46c60a63c2bd6d05d9c39068b35528f549688063ac651822ff24
font_01_sfnt_off0000fbb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB4 11044 bytes
SHA-256: 5aaff4445ca11e05139c43aaaae8a51b691c1e590dc58a22d27c12b33a156204
font_02_sfnt_off0001150a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1150A 18000 bytes
SHA-256: 09d2691b73a0aee527539a40026c61d81e2ee4d4995fd3a5bf994837b6c37649
font_03_sfnt_off00014471.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14471 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1