Malicious PDF — malware analysis report

Static analysis result for SHA-256 8255be6131bf40e5…

MALICIOUS

PDF

86.4 KB Created: 2021-09-14 09:27:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d5caeaeaa26b161eb5423b79be2d3637 SHA-1: 240daa69482f3c83a995ff96c484f971fbf78f8d SHA-256: 8255be6131bf40e512a4a7245b1a485a68fa35385006b728bba8d11e0b876cd9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/dc924dac2729561e3e26449de693a1c4/77882476858.pdf In PDF document text
    • https://motiwalainstitutes.org/userfiles/file/suzop.pdfIn PDF document text
    • https://9ja-bet.com/userfiles/file/xakoxuxatir.pdfIn PDF document text
    • http://888chji.com/userfiles/files/5318179434.pdfIn PDF document text
    • https://dampinggame.com/calisma2/files/uploads/filifokenexeribijeguwep.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613f7be4b8e8c---gorirulawewazofep.pdfIn PDF document text
    • https://adium.ru/userfiles/file/gesufeba.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/negilipirimijazimawek.pdfIn PDF document text
    • http://kozelskadm.ru/files/uploads/files/dowaporukuxij.pdfIn PDF document text
    • https://rosycaffe.com/file/48509674085.pdfIn PDF document text
    • http://linhkienhunganh.vn/luutru/files/59862563676.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/jifazitofafutepotakovoguw.pdfIn PDF document text
    • https://biodent.ro/m4fm_files/m4news/ck-uploads-files/bakodilasulosazojasiv.pdfIn PDF document text
    • https://aymexco.ro/ckfinder/userfiles/files/tuxovakomiminigezovob.pdfIn PDF document text
    • https://seeandhearbetter.ie/img/shop/contents/41977998485.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132b6504af3d---23906149464.pdfIn PDF document text
    • http://teifsepahan.com/files/file/24788445738.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/af1cc3ea05fdec69c7998bad29d8ad71/winikodajezivatowane.pdfIn PDF document text
    • https://zlatartopalovic.rs/files/31551981317.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/pui0k3njd8ogn193imjvofrekg/xaribi.pdfIn PDF document text
    • http://home-hj.com/up_photo/file/79723914369.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=campbell+biology+in+focus+3rd+edition+pdf+downloadPDF 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_off0000e6aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6AA 11604 bytes
SHA-256: 568e9d12fffb366b816200569318f4972b31003d54f72b520a236a22630332a5
font_01_sfnt_off000101ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101EC 19120 bytes
SHA-256: 689ed38aad71befdefb70019cf2457b764394494ef29c79c6f97eb0ea59a9212
font_02_sfnt_off000133d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1