Malicious PDF — malware analysis report

Static analysis result for SHA-256 851f0eca2ff38a60…

MALICIOUS

PDF

70.4 KB Created: 2021-07-01 00:49:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9fda24ab1dae87ff61f302660f5596f1 SHA-1: 6c6feb73433ecfec7363852e807ff6f8bf115694 SHA-256: 851f0eca2ff38a6062fd5ef535ecd5c20b7533842bd34ad1f6a96c57785dc5df
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to compromised CMS upload storage, indicating a phishing or redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the structure and URL patterns are consistent with malicious PDF documents designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/gvab3dqi68ja4tvj9iv48rc0qe/91354523022.pdf
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/kqagvtoolg7letskd38kbr41e3/selavuwaxokejanonebigedef.pdf
    • http://jatyn.cn/upfiles/202106/file/1624884044.pdf
    • http://agendatourvietnam.com/hinhanh/file/zamotajutebiba.pdf
    • http://www.asap-recruitment.net/upload/file/32836669698.pdf
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/c46ada596ce398fc1e8d577202734ba7/18223723755.pdf
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/2ktr21anvnibo0ri7t541ffedn/98310321123.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160934e0bcace3---46168164125.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606de5aa30924---9872750008.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f1abd6580---gekife.pdf
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/6fd8f58eb79fff10f4478b5a7d0770d7/14430898413.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160bcb0173f472---27278460343.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0e63df6e0---lopamide.pdf
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607735c276cd8---fesamupul.pdf
    • http://fbchitchcock.org/clients/8/8b/8bdff38a390027835eb24981312b950c/File/xanugifafumotimex.pdf
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/b2d10d3526704705de02f05ce9518fec/vakabugibadixafu.pdf
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091965c629f6---98289868636.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7908e0aeb5---zafisanarazewexev.pdf
    • http://www.thaiboat.net/image/upload/File/puvovekurigu.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af95c10d5c7---73655386429.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/ugibna38ae72p6g6mq1ntbbkvs/5193271195.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160876ef19be55---35937544451.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d030deadc7---18477250134.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=bf+video+desi+sexy
    • 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_off0000b7b3.bin
cb85ef32d92a37cfeec77f37406b809c19cf3e3d3367b0ff4901d21bff718e29
pdf-font-stream PDF embedded font (sfnt) at offset 0xB7B3 14844 bytes
font_01_sfnt_off0000dd9c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD9C 16792 bytes
font_02_sfnt_off0000f5b3.bin
b45403eb78fe88ca2ca9b0694903c7e671fbd84bdba165c8474cf574de4215e6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B3 10172 bytes