Malicious PDF — malware analysis report

Static analysis result for SHA-256 c758aaa766bb1914…

MALICIOUS

PDF

83.1 KB Created: 2021-09-07 14:53:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 9bc01ffba731b16397d9f1c6837912ea SHA-1: 36dacb73ab71f00e1ebaac8dbc767d5127cce4ea SHA-256: c758aaa766bb19146838cfe7a8dffb8c7f16577c98f4c3766d94955a0553f4da
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://nomylo.ru/uplcv?utm_term=imperative+mood+in+english+pdf PDF link annotation
    • http://abwva.com/uploads/files/69466858705.pdfIn PDF document text
    • http://arunimaflavours.com/userfiles/file/41764087468.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df5dd319d03---kawibiv.pdfIn PDF document text
    • https://nasikampung.info/contents/files/zifot.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/a91bc290cdd746dabcabe7080b95628d/48204346030.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16103e5ec8de20---wupupezimeda.pdfIn PDF document text
    • http://cesnek-vysocina.cz/UserFiles/File/gubazivugonakowovalo.pdfIn PDF document text
    • http://dorrstrechy.cz/UserFiles/File/lasasekaludonelimu.pdfIn PDF document text
    • http://abw10thstreetne.com/uploads/files/87679963931.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/931899332e4d2765d0d2e24da931eb66/32854473775.pdfIn PDF document text
    • http://bnblspecialities.com/userfiles/files/51804360350.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/986ae502250883bb62f9129ea011691c/77658884464.pdfIn PDF document text
    • https://menu2uplus.com/images/file/jisudasusi.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/ketetajari.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/18371863708.pdfIn PDF document text
    • http://flambotour.it/themes/userfiles//files/22533452677.pdfIn PDF document text
    • http://www.hcc-cpas.com/siteuploads/editorimg/file/jejivekuxorane.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/c70dc2a0804697d856d9365f1f9eb6f2/81091441868.pdfIn PDF document text
    • https://emenu.hu/editor_up/20775953273.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210509031744_495031648.pdfIn PDF document text
    • http://apismorava.eu/docs/nokeretudupuxoneposam.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/b57460ff7c49ea49069f031db77a8a8b/latidotutifasumadafe.pdfIn PDF document text
    • http://orthocarecentroortopedico.it/userfiles/files/53158103325.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_off0000dd76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD76 18492 bytes
SHA-256: d7704b187ffba5143a40a834668e30150b15cff1713c1fd5acfc93306d950ab8
font_01_sfnt_off00010d7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D7C 10960 bytes
SHA-256: bd181b6562c7b4589be0ca63bedc2b6ae86ce881cddc40032ec910c40e64eba4
font_02_sfnt_off00012675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12675 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1