Malicious PDF — malware analysis report

Static analysis result for SHA-256 579371e403806b09…

MALICIOUS

PDF

86.2 KB Created: 2021-09-12 18:06:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 61e0eada1ff81eb215f4a5893b6a0332 SHA-1: 2a994d86818d6b622c547b01dae666e8807f9664 SHA-256: 579371e403806b09551828777cd149f4a64bb05742eed34dbd8b1560596c03e8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple external URIs and link farm heuristics points towards an attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 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://crewmak.ru/uplcv?utm_term=present+simple+past+simple+present+continuous+exercises
    • https://dbmotorbrokers.com/userfiles/file/39496359401.pdf
    • http://baigeleather.com/userfiles/file/woxones.pdf
    • https://yptea.com/data/fckeditor/files/dawogu.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16136efc83a0b2---6356201615.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613821b3b0fec---27783414865.pdf
    • http://liweisteel.co.th/ckfinder/userfiles/files/17156058567.pdf
    • http://spartapr.com/images/upload/file/wovagobek.pdf
    • https://darshanam.com/ckfinder/userfiles/files/nijosiz.pdf
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/7937ecd507b0965ff28a979428d76e46/potozazoraranowitolemis.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/161336e2e28ad7---judojivi.pdf
    • http://symbioticlifetech.org/attfile/fckimg/file///20210909145159_148584115.pdf
    • http://eperon-kochersberg.com/img_db/vukekosusunek.pdf
    • https://radekslodkiewicz.pl/files/file/6175900940.pdf
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd672e2c60---28037396902.pdf
    • http://7profi.net/userfiles/file/78946861789.pdf
    • http://walosports.cl/userfiles/file/xuloxafopiliribebog.pdf
    • https://lensmam.com/userfiles/file/81451517700.pdf
    • http://rococosofa.com/files/files/99199716319.pdf
    • http://identik.hu/editor_up/dumejabedu.pdf
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/voxojeletulaxifemud.pdf
    • http://thuexe7cho.vn/upload/files/jenalaxoduvifu.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613588453acc1---25160878875.pdf
    • http://orourkelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wetotawavagizuxibina.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/77e29ec45be5779e0d32b075c6dd1345/42206042996.pdf
    • https://sushixusa.com/userfiles/files/dexikotizusewa.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8a6.bin
72443eb22f5147555637ad26474af8f89b29703dd27cb8947ed5ce51365a04ed
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A6 10736 bytes
font_01_sfnt_off0001015b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1015B 16792 bytes
font_02_sfnt_off0001196d.bin
37d92544ff16de6e381d8d409ebeba1a1d8713c0983f496186f4efb8d8f6c94c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1196D 19252 bytes