Malicious PDF — malware analysis report

Static analysis result for SHA-256 840508d8e864ac57…

MALICIOUS

PDF

74.2 KB Created: 2021-09-03 11:08:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 22251537d9083f0d6a91d3a0d810a75f SHA-1: 40f3e96ce0e8f5a90fa773edf2ee363ebd860950 SHA-256: 840508d8e864ac573222cd97ef91ae2ea434246f73185435d6cc758c22bc1824
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. It contains a link farm pointing to multiple external domains, many of which are hosted on compromised CMS uploads, suggesting an effort to obscure the true destination or leverage existing infrastructure. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific purpose beyond the presence of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://marcelponjee.nl/ponjeefiles/file/39237944722.pdf In PDF document text
    • http://fsnmmaterials.com/UPFILE/userfiles/files/bameluzuvakib.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/45305865386.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/a3c2cd7eb8beae879905b4bdddfa416d/66882878876.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160728d85565b2---bogomugevejinuresa.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/b4d711f5ad471e488eea66d704e7f7f5/nupotawewuwinavuwudezoju.pdfIn PDF document text
    • https://discovercefalu.it/_data/images/file/kizowix.pdfIn PDF document text
    • http://pokewaveanaheim.com/uploads/files/98140585985.pdfIn PDF document text
    • http://teacherandtraining.com/coj_u/KK/userfiles/files/50040542563.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/59002732878.pdfIn PDF document text
    • https://syteq-pro.com/userfiles/file/71421375742.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/78fd25d792f6dabeb7a05d16a9c862c2/bugeriguruweba.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d321d72284---29842336679.pdfIn PDF document text
    • https://ambalatender.com/upload/files/gozawoxofozifogimagazex.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a577f759d72---mutomidovixuwex.pdfIn PDF document text
    • http://panhongbo.com/ckfinder/userfiles/site_eachfun_com/files/xaxamovufu.pdfIn PDF document text
    • http://cedule-plachty.cz/files/file/nivunibakivazovivo.pdfIn PDF document text
    • http://sanchariglobal.com/userfiles/file/pulebomen.pdfIn PDF document text
    • https://led7.ru/file/77188412885.pdfIn PDF document text
    • http://kristenpell.com/userfiles/files/57125207272.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/uro53bdpsbprf091kmg0hk0mp2/lubawulif.pdfIn PDF document text
    • https://robert-zauer.cz/userfiles/file/wimivosojeboj.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1611e4a9e4b267---69506538572.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160810682b03ef---1950027026.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=petsafe+pet+feeder+manualPDF 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_off0000bc62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC62 17860 bytes
SHA-256: a742002bbd164224b3d5bdb8929900e531ec66a2daf143f11d75e21b0dd06ecb
font_01_sfnt_off0000eb0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB0D 10548 bytes
SHA-256: 81c49df8bd87651e5fcfcc72be1ece5906224c16d9f127c065c0d40e20b31fa1
font_02_sfnt_off00010320.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10320 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1