Malicious PDF — malware analysis report

Static analysis result for SHA-256 28b6e3a971084921…

MALICIOUS

PDF

70.6 KB Created: 2021-09-16 11:37:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7e5d03ac3698f9619a1397aa0bfa4cbd SHA-1: 1480124a3a87a4b07d8b1c16c90033982c20f482 SHA-256: 28b6e3a9710849218f13c33d8952dfcb41ae9bc7d35429e9aeb0845aa1b0f6ec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further support the conclusion that this PDF is used to drive traffic to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://wastran.ru/uplcv?utm_term=watchonlinefullmovies+com+pk PDF link annotation
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/jegatewedarusugi.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca9eed62ff---40295005560.pdfIn PDF document text
    • http://shanghaicruiseparty.com/uploads/file/20284415387.pdfIn PDF document text
    • https://regiefranchet.fr/userfiles/files/bizagatokejasalivati.pdfIn PDF document text
    • http://yevres.fr/ckfinder/userfiles/files/84621602563.pdfIn PDF document text
    • https://kede.org/userfiles/file/zuxebos.pdfIn PDF document text
    • http://ozhelalikram.de/resimler/files/98050887151.pdfIn PDF document text
    • http://eyupsifalibitkiler.com/resimler/files/wefunitenukepe.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/p4va6rccpqh4ne09cup1fk7tea/25141545594.pdfIn PDF document text
    • https://themalc.org/files/file/lijimozejajowu.pdfIn PDF document text
    • http://cabini.it/userfiles/files/7680241358.pdfIn PDF document text
    • https://nedimgame.net/calisma2/files/uploads/7162401586.pdfIn PDF document text
    • https://gretajensen.com/ckfinder/userfiles/files/xogositomifimavozo.pdfIn PDF document text
    • http://tootingtaxi.com/survey/userfiles/files/buxezufig.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/1612edee46bcc8---52057348415.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/o9o9jd9dma70sl71je38i0fjnv/zezamavudigefodabuki.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613926ef6a28a---44080750338.pdfIn PDF document text
    • https://alstar.uz/images/shared/file/lezurolixigesej.pdfIn PDF document text
    • http://4darchitecture.org/img/all/75389684847.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/mibamasovof.pdfIn PDF document text
    • 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_off0000b3b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cbcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBCC 10896 bytes
SHA-256: 2d4ca66ce87c4666f6093efdd9feb0885a05e29fe111a3048cf0379a38813ebf
font_02_sfnt_off0000e4da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4DA 15692 bytes
SHA-256: e533aad7f01df2bfb9f43c30b3c57288f4735d13eafc6961ab2c6bd3667f17f1