Malicious PDF — malware analysis report

Static analysis result for SHA-256 8640aa5daa1f1130…

MALICIOUS

PDF

73.8 KB Created: 2021-09-07 15:27:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 030f395eddf1493ce18209592cbe573e SHA-1: 7f5647e4174ba1bc27e141854052cf15a3a4909c SHA-256: 8640aa5daa1f11306ca29a30abd9c87f01ecb7bfd4ffe05e3042dd7a65286ec9
156 Risk Score

Malware Insights

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

The file is a PDF identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and other domains, likely intended to lure users to phishing or malware-hosting pages. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c3ae7898729---kisivedovo.pdf In PDF document text
    • https://stallion-international.com/userfiles/file/sizobudura.pdfIn PDF document text
    • https://nmg.lv/img/uploads/files/dafumararorurax.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3df42e4a7b---maduketibufi.pdfIn PDF document text
    • http://gesgo.de/userfiles/file/kiluzenugitelub.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085723c8cfb0---68321243855.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/fv4aqgcv9f8hvjfi2futuhs9k2/25217323344.pdfIn PDF document text
    • https://coluer.ir/documents/file/divepefigofebebi.pdfIn PDF document text
    • http://sdtrafficticketlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/33271475840.pdfIn PDF document text
    • http://rustproofingottawa.com/userfiles/file/45826720135.pdfIn PDF document text
    • http://hiddenforrest.net/clients/76790/File/sekoko.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160764339a51cf---wagalutojunisujomodowi.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/585b66b802305ea23568ba81c83f47ec/98018548705.pdfIn PDF document text
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/32ff83c1712a6b28589119cae14911c2/31359180595.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/danusagu.pdfIn PDF document text
    • http://architettotoma.it/userfiles/files/49934701501.pdfIn PDF document text
    • http://www.sintsprev-ms.org.br/ckfinder/userfiles/files/wekeboxivejonipipasovov.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160a53a5c690cf---tekepobizixegilimu.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/65878afecff44f8b54d2bef129001a9e/68661795318.pdfIn PDF document text
    • http://gibisch.biz/files/files/lejaxanuxekisosazar.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/wifupebetes.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160dfca57be05a---wemavebutumiralazaf.pdfIn PDF document text
    • https://www.restaurant-latableedevercel.com/ckfinder/userfiles/files/fogatololiziganitosatoma.pdfIn PDF document text
    • https://hotnews.md/upload/userfiles/files/88748615922.pdfIn PDF document text
    • http://hf1968.com/clients/48820/File/24056419199.pdfIn PDF document text
    • http://martom24.pl/martom/userfiles/file/majudebolewagibunet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=libros+de+harold+lasswell+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_off0000bcae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCAE 17284 bytes
SHA-256: 6c47bbcb11f7fbc6ee7fb25282f4bfa25f4e0c32152d4575ca51717092fa8c24
font_01_sfnt_off0000e916.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE916 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001012d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1012D 10576 bytes
SHA-256: 269c27be554aea543591f3ccbd6abcd337d4dc47119ff9f55b75d9def0101788