Malicious PDF — malware analysis report

Static analysis result for SHA-256 79a1d9ba89e67370…

MALICIOUS

PDF

80.8 KB Created: 2021-09-03 00:16:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c4ed50188140c9f1ab657975984b695b SHA-1: 49ad0441606f0155638d3e768d61a32ac7a8995a SHA-256: 79a1d9ba89e6737034b5de53ddf6c31418569bf7ed7dfde412d4e8e0244b23c2
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the extensive use of external URLs is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608c445e16eca---zogosolopa.pdf
    • http://sodrex.pl/userfiles/file/muvapumawug.pdf
    • http://frezerovka.by/images/fxeditor/file/tosalexo.pdf
    • http://agnieszkapawlik.com/userfiles/file/pezanidogupuzupajali.pdf
    • http://harnettcountyhba.com/userfiles/file/vefujedediboletudafisel.pdf
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160e55cc32e7cb---nazon.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609938804909b---rorikifukakulopejapo.pdf
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1611810d80850d---54090908800.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c86542e4e0e---voxat.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/9vnvk5kf72a18nd0451elkvj0m/zexirometukokiga.pdf
    • http://mxagproducts.com/upload/browse/file/40431487554.pdf
    • http://buergerforum-tirol.at/file/38772087541.pdf
    • http://www.bordadoindustrial.com/ckfinder/userfiles/files/79836795442.pdf
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/43669432321.pdf
    • http://areawifi.com/DESARROLLO/userfiles/files/35075923154.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160930c25bd788---75849054650.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/deaea00bbcf754e7b6b759377dffd4e9/rubuwifagetejawurikifabum.pdf
    • http://fsoa.cn/userfiles/file/wixer.pdf
    • https://moto-trend.cz/public/files/fck/file/71793027722.pdf
    • http://schule.havonix.com/ckfinder/userfiles/files/4890815752.pdf
    • http://danchrisjewelry.com/userfiles/file/16784222390.pdf
    • https://aldurra.ly/images-editeur/img/file/65879514705.pdf
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/254816ec76813dd5a34897e2d13fa142/xevesezaxo.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/4173ucktb5tilk7khjo9g78h04/zotegubekukuvenelanu.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/c471da767d88aaff4b622fe568cd5a43/rojefanapu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=2004+subaru+forester+xt+manual+transmission+for+sale
    • 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_off0000d8b1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B1 16792 bytes
font_01_sfnt_off0000f0c8.bin
03e2de24b894482ca5ee10db63c198c8c624ed3b9895c96854b5365aeddcaf87
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C8 10940 bytes
font_02_sfnt_off00010a37.bin
4e89472a8141403437eef870af9f34556ef3bc4f12eb1b67d34f227576a65c78
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A37 16768 bytes