Malicious PDF — malware analysis report

Static analysis result for SHA-256 557e4db1274f876c…

MALICIOUS

PDF

85.8 KB Created: 2021-06-28 09:55:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 834d8ee85524fd686c76913b891c6f36 SHA-1: a7d891eaafced0c8bb67fdb39469260d4c541bd3 SHA-256: 557e4db1274f876c5c8de1f6abf38de9b4b7c2a043ef8b5118395a4be31666d1
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS upload storage and disposable hosting. The embedded URLs and the nature of the heuristics suggest the document is designed to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9d9fe2f92---44718233936.pdf In PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607ffa7e5e37d---61051668844.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/93775896461.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/1a6157c0b20379c2d0e9e0999ddcc3eb/68086453466.pdfIn PDF document text
    • https://feldmann-spedition.de/pics/userfiles/file/susizekotutunimabogidojir.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160d19c20b60e4---47035852373.pdfIn PDF document text
    • http://n2nlah.org/UserFiles/file/nagarupazew.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16089bc517cb2f---22676186213.pdfIn PDF document text
    • http://scales-center.com/shop/fck_file/file/52671045359.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607742bb07cc2---duturisovovali.pdfIn PDF document text
    • https://btcauction.vn/hinhanh/file/bapojib.pdfIn PDF document text
    • http://gernano.eu/gfx/userfiles/files/16273811954.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b39e1a812a4---ponajamu.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e57fc8695b---50817724798.pdfIn PDF document text
    • https://fenixfalt.com/userfiles/file/60419142518.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160c8896a26ce2---xeboresizom.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160794a30e023e---vibujezazijakoz.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076ef318d937---tagazobowurupewosaguwixol.pdfIn PDF document text
    • http://adveotec.com/img/file/10373764016.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/4eef5376dd4643f4bffffb5434fd5e64/54859711791.pdfIn PDF document text
    • https://www.rockfallco.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f23489f15d---77281082969.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/9b47ec7f11b849161da5a76fcc94383c/lijivanafirerinalirif.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085838773487---zoruvesaburepogef.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/9gs9v0m2uhcv30q5lk3qmfqr00/80986073285.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cdd924688ee---11947322635.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=bachelor+of+commerce+atarPDF 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_off0000ed3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010555.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10555 10288 bytes
SHA-256: aff2baf962cc86681dd3bab9fde1db1bc83fcfec27c1b02766bd2fd7f46e3dac
font_02_sfnt_off00011c8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C8B 17292 bytes
SHA-256: 67a5e3a1f51d4e7d585e5c0d1eb25249719987520119d6c741971d062ee1c0a3