Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2d90ca1e219bc43…

MALICIOUS

PDF

62.3 KB Created: 2021-09-26 12:48:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 12fd0dab9f199f609759b7b46a1af9ca SHA-1: c3529cc095b3a4df69650b918e66ad5769dcd33b SHA-256: a2d90ca1e219bc43a63bda036bc7ddcf96b9d05a169d13eacef8d18666dbecae
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised websites and disposable hosting, aiming to trick users into downloading further malicious content. The ClamAV detection indicates this is a known phishing or trojan variant. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.3678

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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
  • 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://hongphuc.vn/userfiles/file/dasezaziba.pdf In PDF document text
    • http://www.mmd.ntou.edu.tw/ckfinder/userfiles/files/poseninaz.pdfIn PDF document text
    • http://sh-ruiyangcpa.com/userfiles/file/2021-9///20219285644706.pdfIn PDF document text
    • http://openendrep.com/userfiles/files/gokogaxiwotubirubejuxu.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614eaaf76789a---19188184684.pdfIn PDF document text
    • http://irinabailey.com/upload/files/46211617002.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/mlhkefg8m999ev92f5lqfhf03n/17937508377.pdfIn PDF document text
    • http://arenda-v-novosibirske.ru/ckfinder/userfiles/files/9768602680.pdfIn PDF document text
    • https://kheops-so.fr/ckfinder/userfiles/files/77907919598.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/fb4ef786ba111d3ac662528eceb19365/vurafimemoboworerekibaze.pdfIn PDF document text
    • http://netisiletisim.com/guvennet/resimlerfiles/28821806898.pdfIn PDF document text
    • http://ruihuitax.com/files/file/gudojife.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ded68aac21---30960494533.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/65404339682.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/xepuvifagan.pdfIn PDF document text
    • https://www.amata.org.uk/ckfinder/userfiles/files/motonoj.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/70468837411.pdfIn PDF document text
    • http://svenskafik.se/uploads/fckeditor/file/56722631895.pdfIn PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/62331923210.pdfIn PDF document text
    • http://rambud.pl/uploaded/file/36085874368.pdfIn PDF document text
    • http://mingmitrcoffee.com/user_img/files/birupupofulumogeroratoj.pdfIn PDF document text
    • https://tranhtreo.com/images/ckeditor/files/88903694208.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/80824909853.pdfIn PDF document text
    • http://xaydunglenguyen.vn/upload/files/e0ee72.pdfIn PDF document text
    • http://datong-travel.tw/upload/ckeditor/files/20210926163407.pdfIn PDF document text
    • https://cargotavio.ru/files/file/lowuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=paleo+rules+pdfPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB102 10296 bytes
SHA-256: f0a730ad3c90a2c112e7338bb714d3c414c45c9a64a9137c2d3cb73bddb72b4a
font_01_sfnt_off0000c85e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC85E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1