Malicious PDF — malware analysis report

Static analysis result for SHA-256 35fe980eb942aa18…

MALICIOUS

PDF

82.6 KB Created: 2021-09-14 00:11:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a7b0901714210475346762fa5dfd15d9 SHA-1: 369d533228db6756508ad10105097d171ae2db69 SHA-256: 35fe980eb942aa180396d294ca23addee1e7386f8ce77cf07a42efb49e86d0af
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous external URLs, many pointing to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://lexxyin.net/files/fckeditor/file/nupilinikosegumadelugotek.pdf In PDF document text
    • http://www.lnk-creation.fr/upload/file/3404276557.pdfIn PDF document text
    • http://jandenzobv.com/image_uploads/file/tavet.pdfIn PDF document text
    • http://preiss.at/upload_files/files/6942913445.pdfIn PDF document text
    • http://a9188.com/upload_files/art_files/files/20210908_034012.pdfIn PDF document text
    • http://thaoduocvn.com/userfiles/image/file/93289746566.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/fojitupo.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/ku27nuh2d3vinlc5hop3ci052k/xizexefexazuvanusetuzod.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/11433274914.pdfIn PDF document text
    • http://qataminational.com/uploaded_files/userfiles/files/48388702897.pdfIn PDF document text
    • https://echipamente-scule.ro/userfiles/file/nutuzujogose.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///14187202621.pdfIn PDF document text
    • https://danielstrehlau.com/userfiles/file/8241245647.pdfIn PDF document text
    • http://ls12368.com/userfiles/file/voliger.pdfIn PDF document text
    • http://krukaiart.com/userfiles/files/gosukurasivurudegetov.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161344d520a361---30826814713.pdfIn PDF document text
    • https://npkfertilizerproduction.com/d/files/82589378932.pdfIn PDF document text
    • http://polaryachts.com/res/wysiwyg/file/xowonilixaripofu.pdfIn PDF document text
    • https://banghenails.com/upload/file/5099207473.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613300a93465e---13276069402.pdfIn PDF document text
    • http://arc-en-cielproduce.com/ckfinder/userfiles/files/91456236171.pdfIn PDF document text
    • https://galaxy-training.com/userfiles/file/65596924026.pdfIn PDF document text
    • https://eletmodguru.hu/files/files/punibarenik.pdfIn PDF document text
    • https://calson.garment-pro.com/ckfinder/userfiles/files/61168217085.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=where+to+find+deleted+items+on+androidPDF 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_off0000dfc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC8 17072 bytes
SHA-256: d2d09bd78c82899077c0788b98292d46f47d5e51b62d3bdcc9da4918a30d9201
font_01_sfnt_off00010c31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C31 10612 bytes
SHA-256: 32ebe0d643a1b23257ce93abaf9f440bc6492f6291713d651f3273c19760d8b0
font_02_sfnt_off0001244a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1244A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1