Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d44771ee8e7ac50…

MALICIOUS

PDF

103.3 KB Created: 2021-09-15 11:50:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d90201f04a9dfa555714170e226a350e SHA-1: 41db0a839ef100e1bc8a2a104127ac30bd05b67e SHA-256: 6d44771ee8e7ac5088dbd5215e33cdccb405862090bde09b946c9a2570ecb494
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate maliciousness, identifying the PDF as a phishing or trojan variant. The file functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised CMS uploads. This suggests an attempt to distribute further malicious content or lead users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://studiosantese.eu/userfiles/files/20567694994.pdf
    • https://diedacorporation.net/freesiafiles/file/samofumupegirugimowufexew.pdf
    • http://dongbanja.com/userData/ebizro_board/file/34155609894.pdf
    • http://taiwan-tsai.com/upload/files/titus.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613e448853b61---891372513.pdf
    • https://www.zolmedis.lt/ckfinder/userfiles/files/64175699439.pdf
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/83575268275.pdf
    • http://wpklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nabejizozijafobe.pdf
    • http://svatba-emi.com/uploads/pages/files/tizonumipepad.pdf
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/0bff5fcae094109d04937f6126165faa/38593751109.pdf
    • https://paulogomeslda.com/userfiles/file/36914521383.pdf
    • http://yuhao-tech.com/userfiles/file/80372786615.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16131ee3db0b6b---75421701222.pdf
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kajojemububugafazomifim.pdf
    • https://angkorphotographyguide.com/userfiles/file/nukegegadatij.pdf
    • http://logiccpacma.com/ckfinder/userfiles/files/zujurigenubekosuw.pdf
    • http://yourmoneyyourbank.com/uploads/File/3831672097.pdf
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/efc4efd98b6385933372130f24b0b312/54225316443.pdf
    • https://conexus-study-abroad-travel.com/ckfinder/userfiles/file/xagakuzabuda.pdf
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/weluke.pdf
    • http://b-solutions.net/userfiles/file/tibekawivajiv.pdf
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/7d38a915b833c8b8856170e5bf997c73/dexixoxuvifetodoxumojavo.pdf
    • http://lisaarkin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/65048548830.pdf
    • https://ksmt.edu.np/assets/ckfinder/userfiles/files/6505290315.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=32768+square+root
    • 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_off00012b30.bin
ae950dfb838871dc798202d921dc0e5692069fa7772e38db05f94bf39b36ec3f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B30 19692 bytes
font_01_sfnt_off00015e71.bin
6657fa9ec6eeba550c086ef3a515b973ac7dd3607fd307eef22f8dfbfd090ffd
pdf-font-stream PDF embedded font (sfnt) at offset 0x15E71 10724 bytes
font_02_sfnt_off0001775c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1775C 16792 bytes