Malicious PDF — malware analysis report

Static analysis result for SHA-256 66d38fa24f0a0c83…

MALICIOUS

PDF

74.5 KB Created: 2021-06-29 15:51:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3c7cb7ff2af1a8890d9951968ef87f57 SHA-1: f5cc0ada80bb0b121585fd5868aebd8e9cfe93fc SHA-256: 66d38fa24f0a0c83af9d63b232c6458abcff81d95fe5daa488305a60358d01f4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm used for phishing or malware distribution. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further support this, indicating the document's primary purpose is to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/6772e9dea1f6305939f9bf6dfced6d4d/26568475637.pdf
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090289f2a18b---55669181899.pdf
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c30788bc80e---58598894649.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160829b3c6aa35---fowigobudapim.pdf
    • http://s8radziejowice-paszkow.pl/userfiles/file/lalogedujogubakifuposarog.pdf
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/m7nob0ripq58utcrnultb6bckv/tawatu.pdf
    • http://hzjksj.com/images/upload/File/jebegisiwasofigubekizemod.pdf
    • http://sutphinsgermanshepherds.com/clients/21958/File/wamajitipobanedovus.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8f1860ecc0---vibikaziganosuziziw.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16079308a97409---19090536029.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607883750e67a---81717173994.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160986c0bcb348---dewajunajuterusi.pdf
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160be1564de170---godiragoxi.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607499fa75ab9---lozotuxasamugipagavowu.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae3c16c2f93---venavitozukoto.pdf
    • http://alternatifmedikal.com/img/userfiles/files/laxizofefepugefesalikerem.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/vil1uubnsrsv0d622h62ajuq91/87113568844.pdf
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/562f76a2b67a51f7c1379289eac6c5ad/zupibajasexizumugu.pdf
    • http://mtecommerce.it/public/news/file/89130504797.pdf
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/199f08d82876a3759d190ae6d6463dd6/66008441123.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/c850b4d59be864be1e7b171ac9de63cd/74919102849.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096e47c79155---65653890560.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607615c90e1c2---wonosudiporalajofuf.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca86619e3d---68715117059.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=bootstrap+4+complete+tutorial+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_off0000c2df.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC2DF 16792 bytes
font_01_sfnt_off0000daf1.bin
bb69146ff5c2571b4bb9eb1f82726afb97b7fb250c88076692a5efdfb231db2b
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF1 15840 bytes
font_02_sfnt_off0001036e.bin
c0499f4af3afcef2ab92287eb434bf576e9998fe90e760143697075731e29bf9
pdf-font-stream PDF embedded font (sfnt) at offset 0x1036E 10908 bytes