Malicious PDF — malware analysis report

Static analysis result for SHA-256 f783b483ffd9dc1b…

MALICIOUS

PDF

87.1 KB Created: 2021-09-23 10:06:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 3a853546a71bcd62a9874af74c76d067 SHA-1: 3ff3a94829d63bb9c0f8e8683ca3674258a0e911 SHA-256: f783b483ffd9dc1b729375f510cd2e67e7fcfdf54d6933bd9d287cfc1bd8c26f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. These links are likely intended for phishing or to serve as a distribution point for further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9939

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://nomylo.ru/uplcv?utm_term=wpsapp+pro+2021 PDF link annotation
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/tgdb4pcvvdcb48oqc12dhf7t0k/50227276285.pdfIn PDF document text
    • http://gostinica-domodedovo.ru/files/15940067982.pdfIn PDF document text
    • http://picart-personal.pl/fckupload/upload/file/4189535141.pdfIn PDF document text
    • http://bkmarine.net/ckfinder/userfiles/files/1632139809.pdfIn PDF document text
    • https://poganyvolgyi.hu/userfiles/file/45287402478.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143a865e1a60---86294654993.pdfIn PDF document text
    • https://fertilizergranulatorprice.com/d/files/ziwafuwokakir.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/69453401027.pdfIn PDF document text
    • http://wakesup.org/userfiles/file/juloxapubizowase.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/degubitasurasikafesanevoj.pdfIn PDF document text
    • http://uforoi.com/app/webroot/uploads/files/80226074765.pdfIn PDF document text
    • http://cbstav.cz/file/54116285171.pdfIn PDF document text
    • http://didula.ru/img/file/77570435084.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c24d88993c---wujuremofefaketu.pdfIn PDF document text
    • http://www.syrahresources.com.au/application/third_party/ckfinder/userfiles/files/29253932802.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/83201823487.pdfIn PDF document text
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/momifuwuruvesi.pdfIn PDF document text
    • http://starinviter.com/ckimagefiles/danesowulas.pdfIn PDF document text
    • https://dongphuchuytai.com/upload/files/womivowuzufusezutufib.pdfIn PDF document text
    • http://lblussana.it/images/file/mosinasimozakan.pdfIn PDF document text
    • https://databaze-zdarma.cz/userfiles/files/94973015562.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/feliwevijarutez.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd124915ae---fojapenedoxugowe.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/lenojarafameleganugegonu.pdfIn PDF document text
    • 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_off0000eef0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF0 18940 bytes
SHA-256: 232ad09929d8ecda42ec87576129a5a71915fcb47bb4dfbd65ac44b6284bac49
font_01_sfnt_off0001206a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1206A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013881.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13881 10060 bytes
SHA-256: 4de225d3aa9ffc8bcef33065b0d68ae388a1a3a8f9a92621082b0eb535353c8b