Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f79d67108bd6635…

MALICIOUS

PDF

72.7 KB Created: 2021-09-29 10:58:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6099c5be5ad679537d55f5a63c34e05d SHA-1: 82f5a431978bfbcd483f68316037b8cf1919dec4 SHA-256: 7f79d67108bd6635e5834ab769ea7ee85410a50384184c64f34b78d62d2b0413
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The primary purpose appears to be directing users to malicious or phishing sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://biogenetec.tw/image/files/20210902_111824.pdf In PDF document text
    • http://handsonmontessoripk.com/userfiles/files/97494358828.pdfIn PDF document text
    • http://citty.org/images/uploads/file/14263884414.pdfIn PDF document text
    • http://hurtglass.pl/upload/file/5242080605.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/pazegaza.pdfIn PDF document text
    • http://sola-brothers.com/userfiles/file/23295514820.pdfIn PDF document text
    • http://meghdoothsuzuki.com/uploads/satubulejupaf.pdfIn PDF document text
    • https://satesayap.com/contents/files/gapobexije.pdfIn PDF document text
    • http://studiotecnicopetrillo.eu/userfiles/files/limifikaweziker.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/202194145583846.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1866715e8---givakusuzub.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141c9927a2d9---78675912625.pdfIn PDF document text
    • http://msiutilities.biz/documents/10036678823.pdfIn PDF document text
    • http://www.afurg.com.br/assets/ckfinder/userfiles/files/17198439904.pdfIn PDF document text
    • https://angkorphotographyguide.com/userfiles/file/67413945494.pdfIn PDF document text
    • https://htcpost.vn/vietpost.vn/img_content/file/48383195732.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/09/files/210922222545.pdfIn PDF document text
    • https://newcar-rental.com/uploads/files/202109100318316805.pdfIn PDF document text
    • http://magdrywall.com/project-new/christianbook/upload_images/file/75372371719.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/25938945688.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16130ebc62b2f2---vulotunizug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=hunk+tv+apk+download+latest+versionPDF 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_off0000b357.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB357 19052 bytes
SHA-256: a002676231bec58993242bb599c58efa05e50007e1797b8257416ca8a1dab3a0
font_01_sfnt_off0000e4ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4AD 10720 bytes
SHA-256: 8a09712a1e468a4407e3d39868e7ce4ab7ca00e244fb7145f9745a4a827e28cd
font_02_sfnt_off0000fd71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1