Malicious PDF — malware analysis report

Static analysis result for SHA-256 13130f12ad93680e…

MALICIOUS

PDF

88.0 KB Created: 2021-07-04 11:03:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d933588dd7a91b71ec9568c96d04829c SHA-1: c9b7ca36197c124d08ea33a60336c73ee2b1fdb1 SHA-256: 13130f12ad93680e4dbead029821d4c9f12d5c9f40dd0da10e3c558e52256e88
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised websites and disposable hosting, indicative of a link farm designed to redirect users to malicious content. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this malicious intent. The ML classifier and ClamAV detection further confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://coretry.ru/uplcv?utm_term=using+tor+browser
    • http://gianniarnaudo.com/userfiles/files/kimolexu.pdf
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/ed7806cde53b1863d4b2065e6f65b25f/xilunujatiwibipuranuva.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/1789763c4e41f4782a70a6c50da107ac/vidilitimiviruxopelifor.pdf
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098c50da6cec---gunezuwuwepu.pdf
    • http://imreelectric.sk/uploads/file/zelifofuderusesagadib.pdf
    • http://bahattinburyan.com/userfiles/file/16685326613.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1606c933738946---96475164358.pdf
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160742083e1df7---51155150425.pdf
    • http://wksystems.net/HotelEstimator/userfiles/file/30174430005.pdf
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/6p8hkprhe4jja3nlqh0ki3ees7/kojupe.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6d40bb8590---27010210354.pdf
    • http://allprintusa.com/admin/images/file/80137880665.pdf
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/24f66da9331f216f5757c69f42b0ea87/24883841928.pdf
    • https://rybczewice.pl/userfiles/file/63344839540.pdf
    • http://kpotplace.com/uploads/files/85885616070.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7599913e2---90346180676.pdf
    • https://devcons.org/uploads/userfiles/files/xifososalatusowog.pdf
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/01a67399ee53cf4253220e1de119632d/34897500196.pdf
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/763b2c98408e7604acc5b6332edc168c/8604964261.pdf
    • http://tafgambiatours.com/userfiles/file/18780194854.pdf
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/qpagthabudmuf8n5p6f29upnib/76833139256.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a567b5790a5---30248278255.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abdc58bf5d1.pdf
    • http://4reality.cz/userfiles/files/zukorozono.pdf
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/2b18d403cbcc0e200527d42346d381b0/ruxawurupusum.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7a2.bin
ca656dd5bba21fa5d0324cea91c478d31ef8d6c2ee763e5d381f5ec68021afdb
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A2 16948 bytes
font_01_sfnt_off00012390.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12390 16792 bytes
font_02_sfnt_off00013ba7.bin
7881fca84c8b40f044be201dc39048847ee2fc7069c7f82bb8927a902d26ce1f
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BA7 10308 bytes