Malicious PDF — malware analysis report

Static analysis result for SHA-256 21dfb7484b0da08f…

MALICIOUS

PDF

70.4 KB Created: 2021-09-30 23:33:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: ff63fc08bd1d308d8ff3b52f1556ef82 SHA-1: 72a6dd68d5149cb5feb1ba611f632ec216bc737b SHA-256: 21dfb7484b0da08f6913c0520e8e1d2945bbcb26d9b317d50d7b5fd3c215fb21
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 websites or are part of link farms designed to obscure the final destination. Heuristics indicate this PDF is a link farm on disposable hosting and points to compromised CMS upload storage. ClamAV and ML classifiers also flagged this file as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://huntic.ru/uplcv?utm_term=curriculum+meaning+in+gujarati PDF link annotation
    • https://reformedgeneration.com/userfiles/file/49752105504.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/d4b9b3a1vvoer74bfq6rebsrva/86531900017.pdfIn PDF document text
    • https://saintarseny.ca/sites/saintarseny.ca/files/file/burigajafugolo.pdfIn PDF document text
    • https://rocksoliddesigns.biz/userfiles/file/suvozigedojowurufo.pdfIn PDF document text
    • http://sangtaoad.com/uploads/userfiles/file/dedanasutasusurugemenexo.pdfIn PDF document text
    • https://k31szmq42-nu28.com/contents/files/79624225107.pdfIn PDF document text
    • https://domilot.com/uploader/files/puzanone.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc139f0c59---pepimolafipisude.pdfIn PDF document text
    • http://kdbelektrotechniek.nl/uploads/file/bijavifeza.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/974ndege8gdb7l66bbj0lnkpc3/56679439376.pdfIn PDF document text
    • http://mientaytourist.com/uploads/files/82484209948.pdfIn PDF document text
    • http://e-pisanie-prac.pl/famprojekt_z_serwera/images/file/23747299307.pdfIn PDF document text
    • https://bselink.com/userfiles/file/pelagakuvakakepedikizirin.pdfIn PDF document text
    • https://okazdedziecko.pl/_files/Media/file/61042037154.pdfIn PDF document text
    • http://donghobaoan.com/uploads/files/nabozesawavitenedegud.pdfIn PDF document text
    • http://saharun.org/uploads/ckfinder/userfiles/files/sosuwarisovatavemojegi.pdfIn PDF document text
    • http://chengzechem.com/upload/files/27873019898.pdfIn PDF document text
    • http://syekp.gr/sites/default/files/file/jofivugejukexi.pdfIn PDF document text
    • http://celeb.huh.hu/UserFiles/File/33286734297.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613e35c526e5e---niketuvokagiwonefolezu.pdfIn PDF document text
    • https://jmcoverseaspvtltd.com/uploads/files/linoxalibo.pdfIn PDF document text
    • https://curvy.tw/upload/files/rilowomakozemukepamasoxu.pdfIn PDF document text
    • http://www.azurwelcomeservices.com/userfiles/file/jokagugukifofuwaviz.pdfIn PDF document text
    • http://westernmaki.com/uploads/files/dixazizemoki.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/38e62e1ac48b32967aef6669732b322b/bupoledano.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/42851747888.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_off0000b44d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB44D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC5F 15540 bytes
SHA-256: a38064b801ed8f06d0fd04815af3633bc7ebafe7c74b39984178fa1505f27a60
font_02_sfnt_off0000f39c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF39C 10544 bytes
SHA-256: d7a0a882d5490b9e9c2d3e3dbf14d92eab8b85a3c3ad7417fd5c0bc1e2af29fa