Malicious PDF — malware analysis report

Static analysis result for SHA-256 de4c78384cb59469…

MALICIOUS

PDF

85.5 KB Created: 2021-06-27 23:03:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 824df5bfe191f658850226427b521787 SHA-1: abaa654e9638f48f7909cc1a2af099cf12b59728 SHA-256: de4c78384cb59469961d643a376884f2eb79a851fac55b189e535e92bb94978f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for exploiting PDF vulnerabilities or initiating malicious actions. It also features a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites, suggesting an attempt to obscure the ultimate destination or leverage existing infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://himalayanthailand.com/image/upload/File/zuginisaparilajo.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607257a274f30---29276602339.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/f4b9af725e3660ec91ff638915925adc/20341077633.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd895ddc1d1---41382653739.pdf
    • https://edcasys.com/ci/userfiles/files/78948864883.pdf
    • https://dbmotorbrokers.com/userfiles/file/82603112582.pdf
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/1nqv8np7691ugcbju2louq11tj/67234228409.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/jhe62lnb84nh5uv4t6g8u97b00/14447611072.pdf
    • https://agrilaui.com/userfiles/file/kegorevadafumaba.pdf
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/6ec2386e3a3be36aaa16258e489a29c6/zujoviletiwikuno.pdf
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/43304f14e0dc3b784d0328fd6f5ab2db/vokajatebafet.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074892393ea2---44349082717.pdf
    • https://sgcaregiver.org/contents/files/37483537696.pdf
    • https://dichvumayphoto.vn/webroot/img/files/49360918118.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/08bb9b2dd6efc84ad1e187f34dd9c2bd/18408269999.pdf
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160b826717164b---nemixupasujaviwovamejo.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160739c1e75f7e---9637718674.pdf
    • https://soyana.de/js/ckfinder/userfiles/files/98328761220.pdf
    • https://szekszardportal.hu/userfiles/file/51703276452.pdf
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/843a662634bd72f45d0c69692fdafd1a/zobikumirujorasisij.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c636bf115---82492138471.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16096c3fcd1ac4---47350476165.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c47278aa47---36341348561.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=yellow+fever+prevention
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d7ec.bin
9a16018fcce1074b4cb6cf5e8cd30c9345645a29c73e5af804d727342b5ffa39
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7EC 16872 bytes
font_01_sfnt_off00010408.bin
50525ce20c388862541099897196693ca0ee040eef1519e1692042723497b431
pdf-font-stream PDF embedded font (sfnt) at offset 0x10408 10156 bytes
font_02_sfnt_off00011ad4.bin
5e4c00560aa92e58ed7893f1d29e19bab1551ecfc1a2d4366013d39ff1dff337
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AD4 16092 bytes
font_03_sfnt_off00013011.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13011 16792 bytes