Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d2315794bd43e26…

MALICIOUS

PDF

68.8 KB Created: 2021-09-19 22:51:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3a467c0ad03b08ad8c06b6e0c80c865a SHA-1: 7ff5255b04446cea571b380d99857e2f8903f46e SHA-256: 3d2315794bd43e2601fecdc28f5291df70befa7e83ed49f2dd87ad65ab8a6017
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm. The embedded URLs point to various domains, some of which are associated with compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious intent, likely to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://yuh-tarng.com/userfiles/file/90321224171.pdf In PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/mro1190tj0u0p7pcm9ssagjc7c/12862264259.pdfIn PDF document text
    • https://tylbm.com/Upload/ckeditor/files/59680059030.pdfIn PDF document text
    • http://tareeapartment.com/user_img/files/xudozisututuvat.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/xolije.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/94973585811.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/6e6da2693470f756657cdf973a42cb1e/sirapajosewovidipesanus.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161458d219f798---52805516541.pdfIn PDF document text
    • https://carolinevlieghe.fr/images/file/47934055530.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16138fac1196c9---82202455304.pdfIn PDF document text
    • http://sambometal.com/dataroom/file/36401062941.pdfIn PDF document text
    • https://skvely-kup.cz/files/file/bopaj.pdfIn PDF document text
    • https://ddc-touggourt.dz/ar/files/denenulejuti.pdfIn PDF document text
    • http://versobrokers.eu/userfiles/files/ropijeporiluvopogax.pdfIn PDF document text
    • http://dintainoodle.com/uploads/files/jamovolidevuxunama.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/bmkep1niampa517b2e4o5baba3/bifevujo.pdfIn PDF document text
    • https://windfreeklima.com/upload/ckfinder/files/57051333421.pdfIn PDF document text
    • https://hantverkarenisandby.se/UserFiles/files/71688820976.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/83634862787.pdfIn PDF document text
    • http://bresky.cz/res/file/43844537078.pdfIn PDF document text
    • https://yourdentist.ro/app/webroot/files/userfiles/files/91791759532.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=words+that+start+with+a+vowelPDF link annotation
    • 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_off0000ae27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE27 10384 bytes
SHA-256: 25d939a959da37c1df2bd5526912416664d8a0405c0bd2e16b9ec31d85fbccf6
font_01_sfnt_off0000c5da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ddec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDEC 15888 bytes
SHA-256: 950cc9fe15002d052068363782a297646d63ebf1033e717aa6807a25cd7472d9