Malicious PDF — malware analysis report

Static analysis result for SHA-256 755519f9a718b96f…

MALICIOUS

PDF

78.3 KB Created: 2021-07-02 02:59:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 0a2f2ffa8ddac887131d92d0399a7c50 SHA-1: a917d8c0b2dfadfb3617025a036c86bd03b08a09 SHA-256: 755519f9a718b96f6ec88853326161834b24d973ecdf7506b1f21893407dbbb8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress upload directories. These links likely serve as lures to redirect users to malicious or phishing content, a common tactic for initial access via spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/8d7c994090d340cd0cff9e2819d8b85d/dinenowoxalin.pdf In PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/gadhc2qv6ah5r6tgc2e38sm8m0/69692172441.pdfIn PDF document text
    • https://vieiras.pt/imagensprodutos/file/vipovu.pdfIn PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/5c5ad657e165c80e7297fcca85bdb452/88644006825.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/54353607dc532197b9beb5f159b290f0/tefawozenipodixemepavifi.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/de6fd24f2537244c5984e7cee24859b7/diwako.pdfIn PDF document text
    • http://pogservice.ru/userfiles/file/falisefedepirerubudaxubit.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/lkcnb0n1gsguh94lgh6ss8ah81/xedaruvadusabofojag.pdfIn PDF document text
    • http://qiuyutv.com/userfiles/files/20210603124752.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16085abe43347e---xarepojudopubalupepop.pdfIn PDF document text
    • http://innovad-ltd.com/userfiles/file/91809648965.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/812ee529c8e91aebe8264d9eff5fc52b/79191044191.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e11ccead7---3869917780.pdfIn PDF document text
    • https://btsmstlucia.com/atomicsteps/upload/userfiles/file/xipivik.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/ar774llv1acdab35303dununk0/misozivipefof.pdfIn PDF document text
    • http://doo-san.com/userfiles/file/20210701064738.pdfIn PDF document text
    • http://anbao.vn/uploads/userfiles/file/zizemunarexusaf.pdfIn PDF document text
    • http://ekolojikweb.net/upld/userfiles/file/42305873260.pdfIn PDF document text
    • http://apluskleaning.com/admin/images/file/74472952819.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160ac02ccf1ce0---75168369115.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075c8c6081bd---bawepubimegodemuvexip.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/vpq96a5hl7pdpp0ct7i09lass5/vegulixose.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/9347934c72d564b25db377102415b21e/40901440184.pdfIn PDF document text
    • http://aozbt.com/clients/3/33/335f642cf73e2ad82edc7dd4a76dad4e/File/63611112714.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=howl%27s+moving+castle+full+movie+eng+subPDF 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_off0000ce1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE1B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e632.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE632 10996 bytes
SHA-256: c9deb5d7ec8be2a11fdbcd6be8eae4c0a03cf34547780907b72fa88d68d75c4e
font_02_sfnt_off0000ffd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD6 17040 bytes
SHA-256: c637c8d1e23c80f0c2ff7fb58d7e91bebaaf4c95f862aa3e32ec84c77e22967e