Malicious PDF — malware analysis report

Static analysis result for SHA-256 79875e8b877ac6f5…

MALICIOUS

PDF

89.4 KB Created: 2021-07-23 23:59:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: c456be1f42ef7fdc518795287934dcde SHA-1: 8875016f802cf2e95e0f674835a9c79460767436 SHA-256: 79875e8b877ac6f58a74d3354c74bacdf08c5f9b2236987848dc1ad28cab0ae2
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting a phishing or SEO manipulation scheme. The embedded URLs likely serve as lures to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607b207247a8f---64412787289.pdf In PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/da7b7567b282cb626cce39ac046dc553/zanubasuguluranekamofobem.pdfIn PDF document text
    • http://mstreatmentadvances.com/userfiles/files/ruriferes.pdfIn PDF document text
    • http://hyperasp.net/userfiles/file/jozumevimadadut.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/71fa7b8ec7e1767a7c0fa69467673ddb/39354255506.pdfIn PDF document text
    • http://polimak.pl/userfiles/file/nunujifidamigufomilanaw.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/5ss723ngm4b6evi125o4q5nce2/latobemokatezutokakawu.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/4e6c7d22b1933465816b583692de1f33/87480700343.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc9ef5f11b---xowotodejujeraw.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0a3d9971ae---ravak.pdfIn PDF document text
    • https://calmoinc.com/upload/editor/file/16103334761.pdfIn PDF document text
    • http://xn--e42bt3l.net/upfile/files/8064451410.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/ba591287318d177b6df6d0867c119566/tovini.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c7f02350893d7ab28b746dcb0606d460/ninapakukeperezegujaxe.pdfIn PDF document text
    • http://ajivikafinance.com/userfiles/file/mulowurevosugadegated.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/3cv1mlv6kmliqk9sg1v9nab3q1/12051442633.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/305ae1ec77c0d20c7df4421ddb3cc8a9/lodimunafegatus.pdfIn PDF document text
    • http://pospatrans.cz/UserFiles/File/72612076098.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202107072354522348.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e4b510ff3---nadufawiruza.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/c9049baaf140a693a34577bd8abb911a/relomoguveturotefex.pdfIn PDF document text
    • https://angkortaxiservice.com/userfiles/file/40407514618.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/sejixog.pdfIn PDF document text
    • http://www.deopendeur.org/imgUser/file/22784690730.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=how+do+i+reset+my+onn+bluetooth+earbudsPDF 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_off0000f848.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF848 10944 bytes
SHA-256: 80e8cd24a5224e730045527e1005d3361fddecc7126265ded7ec2fafd16e524c
font_01_sfnt_off00011176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11176 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012988.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12988 17396 bytes
SHA-256: 0ca525a0345bd3e91144a21c0bad1491a6022f4bec428a3a7ab324abf490cd51