Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1f9ebddbba3d83d…

MALICIOUS

PDF

76.2 KB Created: 2021-06-26 01:16:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 642eb7e30e3bd47c2e8162bda65c7b08 SHA-1: 4afbb3b271b6423596daf7e5cdfecdf3d50d3a2f SHA-256: a1f9ebddbba3d83db93a96510dfa57d3078b3248ab1c8d1ee49ad0918fc878d8
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories. These links likely serve as a lure to download further malicious content or redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16080aa7c5c1db---texepifezuxedigivujazuk.pdf In PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/5bf77cb14b0ceb73602cdeb85b50bd20/98156982948.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/6093ddd43920bb11565184d242cf42f1/72710405087.pdfIn PDF document text
    • https://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/af22ae4173316c6d107441789bd12475/63986657454.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/1ceed81b27c371abc00dd36048ef0d9b/49067505585.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160ad659336d93---dajusajabo.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160712e111b696---2223604399.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/c1df51107b79054bd1d60099943b2685/7620714558.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607185e3f0af0---97849126158.pdfIn PDF document text
    • http://au-zlato.sk/upload/files/27548632094.pdfIn PDF document text
    • https://arerp.kr/data/file///76031076034.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/d6fbe51744712311762adca6d1a7452b/42366791051.pdfIn PDF document text
    • http://cuatro-pr.org/sites/default/files/file/76212245551.pdfIn PDF document text
    • https://areicon.com/images/file/zijemitovuz.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b851e396040---66518107836.pdfIn PDF document text
    • https://teenvolunteerhouston.org/wp-content/plugins/super-forms/uploads/php/files/b8832460bcc3dcb16bdc77a1c7091b41/46811386130.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/5483216219.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/51f08cb8e5c970d33ff79a11753d2bd0/javidirori.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a4d8a2ad5---bajuxirifewaxunufutikukeb.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1e256dda16---22562351932.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608530fc7fcf8---govutipenare.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/48990450236.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0ea9ddf94e---jasonurezuz.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a8670e871ae---vaxuwuwutupukonad.pdfIn PDF document text
    • http://waterlootour.com/FileData/ckfinder/files/20210626_5A1E619416483896.pdfIn PDF document text
    • https://petikdaun.com/contents//files/51152803648.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=word+to+pdf+easyPDF 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_off0000c6ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6EF 16616 bytes
SHA-256: 9be7b7f07e0be98f29c76645892ac6d654dc18271b1de1150a69716d0033ef5a
font_01_sfnt_off0000f22d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF22D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A44 10356 bytes
SHA-256: d878388e00424d649af2a567c910ccbd3884426aa4e893838cfeca54298f7057