Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f3313140b48b46e…

MALICIOUS

PDF

76.2 KB Created: 2021-09-08 08:50:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d497f43b6ef3c392d5a55830ad53702b SHA-1: 2976d46ac95d3d58d060bbbe90c9048b343f5c09 SHA-256: 4f3313140b48b46e72d91cdbf8ee622133dbbb490ac4dc16b0f45aaeea2d68ec
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites and disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and link farm characteristics are consistent with attempts to exploit user trust or search engine optimization tactics to deliver malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://fskyok.com//uploadfile/files/ridimekategor.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc5a845450---lofunetunafasefakoxexogun.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1610e397d1d901---72690409657.pdf
    • http://ats-dz.com/userfiles/file/zumadadadusutovaxoka.pdf
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad9e02657f---87701834759.pdf
    • http://zoncmswebsitebeheer.nl/files/editor/file/kaberivakomanegawomelid.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160b78072ed597---26522468766.pdf
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/93832685093.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608a2d9f1136d---zekodimipadinebinolijixom.pdf
    • https://khachsan295doson.vn/namthuan/images/news/files/49567165523.pdf
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/63k1uii1087gkc2eb5oc3pn4p1/xutalirulujak.pdf
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160fbbba596e9a---fedoxope.pdf
    • https://kede.org/userfiles/file/13838491184.pdf
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/13b3f8c3e886774836d76688569f3f08/21041006490.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b3e66f56340---81784311491.pdf
    • https://weddingitaly.jp/images/file/bovoxuvegiwofimujal.pdf
    • http://lakesnwoodskerala.com/uploads/file/vebilowikelawipu.pdf
    • https://eguiders.com/uploads/313681629.pdf
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a14520a23---xaxokevam.pdf
    • http://flygarfield.net/userfiles/file/kadepa.pdf
    • http://karlsbach.de/userfiles/files/77722945171.pdf
    • http://artospace.com/pics/file/vanigojokoro.pdf
    • http://joesservicecenternj.com/userfiles/files/liridag.pdf
    • http://studiogiamberardino.it/userfiles/files/mufolipajanupakisiru.pdf
    • http://ecohort.com/userfiles/files/bekuzizenemakerojabem.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=how+can+i+unlock+a+pdf+file+for+printing
    • 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_off0000c669.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC669 16792 bytes
font_01_sfnt_off0000de7b.bin
0b618b72d79492d86627580121b38d5e5b512b8a13492b179e873532e0cf2183
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE7B 16712 bytes
font_02_sfnt_off000109b2.bin
c642b4bc789ff6460b5c388e1c9d2791b58559bd1b1e32a907367144ad9b94bc
pdf-font-stream PDF embedded font (sfnt) at offset 0x109B2 10896 bytes