Malicious PDF — malware analysis report

Static analysis result for SHA-256 8904701dc5c01beb…

MALICIOUS

PDF

83.2 KB Created: 2021-09-03 21:29:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ef2395b838c5f0fd087a0defb7e5e1b9 SHA-1: 066642e214657bf5fdf6064fdd54df6ca57434ee SHA-256: 8904701dc5c01beb41bb910da19c091bd99483d22540cdfe1cb99b12998a0cc5
156 Risk Score

Malware Insights

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

The sample is a PDF document that functions as a link farm, directing users to multiple external websites. Several heuristics indicate that these links are hosted on compromised CMS uploads, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9448

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://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/335beaa5be011666f3feccd141b8cbdf/84914416717.pdf In PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160bf8b2bc11cd---sakexitewupi.pdfIn PDF document text
    • http://windmill-bv.com/userfiles/files/vusokopolujiv.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa043c7461---wekirugipiduturosi.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/rigamupar.pdfIn PDF document text
    • https://actor-conseil.com/files/file/58709502358.pdfIn PDF document text
    • http://industra.sk/userfiles/file/52260847586.pdfIn PDF document text
    • http://www.tokyomagic.jp/images/library/File/xosetiworiv.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160f9cb9413c78---xafimedesojibu.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1612849829ed3e---kovobojimukorojiketeman.pdfIn PDF document text
    • http://abwingsva.com/uploads/files/27654377943.pdfIn PDF document text
    • http://philboyd.com/fadevigapagigasilet.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/6485986449.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/ad91ebf31172770fac8da5429bef2e5c/10258946837.pdfIn PDF document text
    • http://cozycornerexpress.com/uploads/files/90301076350.pdfIn PDF document text
    • https://leganordavigliana.it/uploads/file/2050694270.pdfIn PDF document text
    • http://hornets88.com/clients/56662/File/38348202133.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b0d493e0bd---sisomimefawu.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/5e0e8fe1e5eed84824f6b9c3577f5438/xobetimakadikobebewa.pdfIn PDF document text
    • http://www.siposferenc.hu/html/43159855970.pdfIn PDF document text
    • http://szpital-sulecin.pl/images/fckfiles/file/70012820781.pdfIn PDF document text
    • http://burelomdo.com/ckfinder/userfiles/files/8840595284.pdfIn PDF document text
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/3580fc1382e0b973453b01d77771cd15/25046531450.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=diferencias+entre+socialismo+y+capitalismo+pdfPDF link annotation
    • 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_off0000e258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE258 20316 bytes
SHA-256: 03b78ffa7e2ee600f81534b4f41a051eb62acd30611e08a4df01143e81756061
font_01_sfnt_off0001154e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1154E 10896 bytes
SHA-256: 532555906f210fa11a589579d9a5cb5c53ac83a823219e73679d3786d12b83b9
font_02_sfnt_off00012e8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E8B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1