Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c53efae0e61df91…

MALICIOUS

PDF

88.7 KB Created: 2021-09-18 08:17:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: df0cc165e878175133bf574d4394acda SHA-1: 7b7616bcb8b2934dc228b87efb46706cbae3c594 SHA-256: 6c53efae0e61df91347d54c7fafb9173c03073498352401b9cf4fb8ceb2e932d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting. Heuristics indicate it functions as a link farm, with a high ML classifier score and ClamAV detection confirming malicious intent. The primary purpose appears to be directing users to potentially malicious external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://rapet.hu/files/92855212140.pdf In PDF document text
    • https://iqrainternationalschool.org/_assets/files/98256291642.pdfIn PDF document text
    • http://xn--b1afklwjc5g.xn--p1ai/ckfinder/userfiles/files/juwidenadowuzowesu.pdfIn PDF document text
    • http://mutamobilya.com/images_upload/files/96198791689.pdfIn PDF document text
    • https://nasco-ye.com/uploads/file/93806861598.pdfIn PDF document text
    • http://szjglaw.com/uploadfile/file/2021091418145373499.pdfIn PDF document text
    • https://qfuse.it/images/uploaded_files/ckfinder/files/1631850451_bfef4923f1.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/49179628331.pdfIn PDF document text
    • http://groupkaishan.com/d/files/92579113454.pdfIn PDF document text
    • http://manilag.com/FileData/ckfinder/files/20210918_5832BBA6C2458E1E.pdfIn PDF document text
    • http://tycoonmedical.com/userfiles/file/16110102497.pdfIn PDF document text
    • http://dreamcatcherltd.com/userfiles/file/texopuneletaxu.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/1666270015.pdfIn PDF document text
    • https://htijsr.com/userfiles/file/nibanafugirapexefewamoko.pdfIn PDF document text
    • http://women-for-marriage.com/ckfinder/userfiles/files/17403789934.pdfIn PDF document text
    • http://lpsa.cz/userfiles/file/gewetizadapedaseg.pdfIn PDF document text
    • http://qhzs88.com/admin/fckeditor_upfiles/file/2021091412032680554.pdfIn PDF document text
    • http://stimatacasa.eu/userfiles/files/3483340326.pdfIn PDF document text
    • https://infotechloyalty.com/bot/ckfinder/uf/files/vunobo.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/dewujaz.pdfIn PDF document text
    • http://labotinnghia.com/img/files/visubuwulevefufebekor.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/ac718e41c5f596ae1a243bdc8038503e/37697789840.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/65bb4e0f14024a0aee52e4c9b575ec8f/nuzugudopomugenojidenadov.pdfIn PDF document text
    • https://kontiko.com/ktkweb3/images/upload/files/43530712112.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139c469b9646---34051588262.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/34058855083.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/93035178199.pdfIn PDF document text
    • https://lapakunited.com/contents/files/77444137770.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=war+of+the+lions+pcPDF 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_off0000f40d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF40D 18876 bytes
SHA-256: 61453e8bee661277a9111cec105cf79235a9fd16d9dd2fa31e1a04878dd3d11d
font_01_sfnt_off000124bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013cd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CD3 10572 bytes
SHA-256: abdba6372a23f71efde6bd91d809de49f9c0165eb232ee80f252cab1f06d1f4d