Malicious PDF — malware analysis report

Static analysis result for SHA-256 241fd3d1769e94c2…

MALICIOUS

PDF

82.4 KB Created: 2021-09-05 21:11:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 14dd8e6f7e4bd982d5b96f4b7ef793c4 SHA-1: fd34da15e4eeb232090771b95036c3369d445603 SHA-256: 241fd3d1769e94c23ec0d2129ff8be02c164435c20820570ea9489a9675879da
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains a link farm pointing to multiple compromised WordPress upload directories and disposable hosting sites, suggesting an attempt to distribute malicious content or phish users. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/25d9827cad47b3ae6ce6a8653b9ab062/vuvoxabimetudegemomel.pdf In PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/hp6apa83jib2pi9h5l918tda84/monijow.pdfIn PDF document text
    • https://winpoasia.com/ckfinder/userfiles/files/17255627509.pdfIn PDF document text
    • http://cdio.vn/uploads/userfiles/file/danubotapepokapomes.pdfIn PDF document text
    • https://fallahi-sch.com/userfiles/file/53541326054.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/7834564226.pdfIn PDF document text
    • http://modero.vn/upload/files/nupofoduwimatebureriveloz.pdfIn PDF document text
    • http://tantusmarina.com/UserFiles/file/geroxijesexaleliv.pdfIn PDF document text
    • http://thelonerangerfanclub.com/ckfinder/userfiles/files/93555210246.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/54ef612c4eee3bfcf6c503297bad2f14/3322590253.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/2c5dcf9215b602c5447d9c58df18119d/32741372013.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc8b996343---42803344840.pdfIn PDF document text
    • https://huaienclinic.com/uploadpic/files/wololujeletiwujizisimaka.pdfIn PDF document text
    • https://sanidom.pl/img/file/fivagejajuwurenedudag.pdfIn PDF document text
    • http://restravel.ru/ckfinder/userfiles/files/94567270240.pdfIn PDF document text
    • https://chupwo.com/editor_upload/file/mosoleverorenizakavub.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/fa0c22b4dc0970f3f9b5506251e3640e/xemokawixedadadizib.pdfIn PDF document text
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/39bcd522fb9d19ddf3f1ee3ca0efb026/91374142409.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/e4ttf51tfaogivr8ei7udio8co/55510024648.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607585c4a4cb7---ponusexametori.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=cutter+blade+design+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_off0000daaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAAA 18744 bytes
SHA-256: fff9911febf0989106d75c8b6312f2e77cfae29902cb8388b6f873293663d2b5
font_01_sfnt_off00010b82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B82 10824 bytes
SHA-256: 9ae602b4062b4316e3db7d2a637821cd4087e634fba28f0c71678460caba562b
font_02_sfnt_off00012426.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12426 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1