Malicious PDF — malware analysis report

Static analysis result for SHA-256 c853731fedc3a8bd…

MALICIOUS

PDF

85.3 KB Created: 2021-07-27 18:43:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e25781fb6c95f4d2b6b7dc3d111b6196 SHA-1: 6071ca558bba747f5f002c58dbf9a12cf3e1d5c9 SHA-256: c853731fedc3a8bd8a21742a402234fdcd196068f17660348cade77c862c97bc
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised CMS upload directories, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable, but the heuristic firings clearly point to a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://thingsantiquesla.com/userfiles/files/teketuluwaminida.pdf
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0678f54daf---gasigixelebixodixoset.pdf
    • http://shopcloud.cloud//ckfinder/userfiles/files/12231225015.pdf
    • https://rugsinc.in/UserFiles/files/siwinuluboxebotere.pdf
    • https://biovuspharma.net/userfiles/files/nonukizorijoza.pdf
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16086d424089d7---solofoxewajupupevesusa.pdf
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/lsg3d87oqf93b1c6l0tof834mk/reganakasabelebop.pdf
    • http://siripanyalamphun.com/user_img/files/50649417449.pdf
    • https://washlounge.in/ckfinder/userfiles/files/pisukabigesibubig.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160dfa99e1f20e---59374096628.pdf
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd2424a263---9265486560.pdf
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/ae46db24e36e9fb01096d19e8f37fa34/52134460611.pdf
    • http://immobiliareborghi.com/userfiles/files/64232260964.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acb893e5e66---pokiseku.pdf
    • http://datavincity.com/uploads/ckfinder/files/kexawe.pdf
    • http://amphorabeautyclub.com/campannas/file/mamewapotigaruxedomuz.pdf
    • https://arerp.kr/data/file///zesufomo.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607066e694379---sutezalowe.pdf
    • http://benthanhsgfarm.net/images/uploads/files/zimofabopegowagofen.pdf
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/579f40d6f67532bcc6611aca03a66302/riwemi.pdf
    • http://dade666.com/userfiles/202106file/2021062022043670554.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/3c19421ac3ef978fd58d44148bbea3fc/lelukipeputimusepija.pdf
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/85881dbfd2322bc5091ded8f888cc0c8/juwigesebo.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=everstart+maxx+jump+starter+600+amp+instructions
    • 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_off0000e688.bin
124eea6d60213a78575e3549d41e56c725b1a5498fe9561a6cdc24d11c59e270
pdf-font-stream PDF embedded font (sfnt) at offset 0xE688 11160 bytes
font_01_sfnt_off000100a5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x100A5 16792 bytes
font_02_sfnt_off000118b7.bin
2ae525c83a1eda042f1ac4d2ab30bf916c0ece134a93ba95df4da73dee0d486b
pdf-font-stream PDF embedded font (sfnt) at offset 0x118B7 17424 bytes