Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8a1012f30881615…

MALICIOUS

PDF

82.7 KB Created: 2021-07-18 20:45:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 810742c00d4100b7a1756e0fdc08b6e8 SHA-1: 68a622fde0febac9d0d0f6778f07793f7417119b SHA-256: e8a1012f30881615b3cf390e03e9a19353ad47d700615df9e06e4c04cb8270c1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution by redirecting users through these links. No specific family was identified, but the technique of using link farms is common in various phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/d73c9b7b231064010a86872f63aaf70c/jezalarowisu.pdf In PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3da56e73c2c8a9261f06ef44c773b995/magivasoramikesoner.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ef76c22244---sorawaxuzizolofelevose.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/48759447503.pdfIn PDF document text
    • http://shangrilayunnan.com/ckfinder/userfiles/files/94876429407.pdfIn PDF document text
    • http://havefuntogether.com/image/upload/File/4512884113.pdfIn PDF document text
    • http://m-styleauto.com/js/upload/files/mixabokekimetazig.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/wasut.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c8fa90eb281---61615432138.pdfIn PDF document text
    • http://nagymester.com/userfiles/file/17155764118.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099a5bff1bdf---kodudowarituk.pdfIn PDF document text
    • http://zzliuxue.com/upfile/file///96637598586.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d97c7b1a314---wafep.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/19mufl6si4is0eppq7e8n05u05/fuxirerolarukuxozoxixuxar.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160775ac53929f---60237710603.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16082db1ce5df2---mudanomet.pdfIn PDF document text
    • http://unseretochter.ch/images/file/ziteroponenanekar.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bde8d262aa7---towipepizudunaninuzoz.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d8a8c520eee---95638785217.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/25034415450.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/f79a2a27ee90a97a1224dc9c4fb535fb/76662498624.pdfIn PDF document text
    • http://rotarybrescello.it/userfiles/files/vijamapujemugovukabit.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/a5d10fdc04fd4b552208b69c8be33755/motatafodizamuput.pdfIn PDF document text
    • https://vinniescustoms.com/userfiles/files/zedaronetetibexor.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/d7omi09h8jevp6fpl19dvro1db/6882452346.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b53fc5f1289---manenubezujopime.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=universal+gas+constant+rPDF 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_off0000d9ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9AC 19084 bytes
SHA-256: cb790f7349323f50c7fe34b4c15186ff43a990569ef568d7f9282c428f5053ad
font_01_sfnt_off00010b7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B7A 10476 bytes
SHA-256: 39675a3f7ea9bca7d8cefaf8a50ee8c86fe2c34e0b3f56740715905b28a6cdff
font_02_sfnt_off00012378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12378 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1