Malicious PDF — malware analysis report

Static analysis result for SHA-256 8243bbc79a0dd9c6…

MALICIOUS

PDF

88.9 KB Created: 2021-07-01 16:54:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6fbfd5b1f723822d9b649744866beba2 SHA-1: e6a9b94cf7de832fba12b8044fd147b4edcee2da SHA-256: 8243bbc79a0dd9c6d323e35881e86bb1a4da2f48ab143da3bc76a9c818ef4962
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Multiple heuristics point to the PDF being part of a link farm hosted on compromised or disposable domains, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of attempts to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160ccd05fe8727---47053533666.pdf
    • http://asiavent.com/UserFiles/file///logaremubofozixakevef.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b87a3017857---tomoxaf.pdf
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/ksseatbdfuiji2v2pf1fh8j357/domugurigerowedudazupu.pdf
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/zukuzakazanar.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d10814433---92094746756.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/4ht5622vh1rnrbg372afoajk09/79408502886.pdf
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16080a14a29664---74296321952.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160881c53ec1f8---woverupojigal.pdf
    • http://reicar.dk/userfiles/file/lidexepob.pdf
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16078f1032d096---6182910440.pdf
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//genenef.pdf
    • https://ildiko-szepsegszalon.hu/userfiles/file/tasilusasadavarokumav.pdf
    • https://intrigantka.ru/images/userfiles/file/45114652700.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d0fd5cdde---23986414685.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/1d9cb9b39548cd717a569f2626249efb/sixamezowukemosufidiluga.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/cc0a7ee1ef5cd7bf84a2cc7db35728ee/18030268395.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/bc16556e0bb265795d69b39951de1bad/74568841115.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f60778a599---lobedolizedo.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/1bmtjdccpnp0343cmquvsfoulb/53349024786.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/16082cd5aa9f61---vijin.pdf
    • https://anjingliar.com/contents//files/4689851537.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=best+yugioh+game+for+android
    • 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_off0000f8c2.bin
6c7d16a5e552c35a51587cab0166982511cada40347a25cea8bde9ffc6749243
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8C2 16552 bytes
font_01_sfnt_off0001238d.bin
9d87aaef982fd1d87223ba6e961d8455b29065a4c9ce590b08ac5145d8f26560
pdf-font-stream PDF embedded font (sfnt) at offset 0x1238D 11024 bytes
font_02_sfnt_off00013ce3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13CE3 16792 bytes