Malicious PDF — malware analysis report

Static analysis result for SHA-256 4451c46384a0987f…

MALICIOUS

PDF

83.4 KB Created: 2021-06-30 19:54:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: d728e7448eb4acd4fdb06521c1143bfb SHA-1: 51105e9d3cef8e80f2f76bc4e43946a3831c113a SHA-256: 4451c46384a0987f46d259a56ca635caef3fb4d1e8078b5a387efd9dfc82b4fb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress upload directories and disposable hosting. This suggests the document's primary purpose is to redirect users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b72172d3ced---28278121599.pdf In PDF document text
    • http://shopexpert.com/app/webroot/files/userfiles/files/bovujimizenufaj.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4b2de68ccb---17477302710.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16071e22bc36dc---76682569827.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609631ac9416e---44599219947.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/aqhv7n2jmdkllkghm4n7sgf184/mabivuvituwejojof.pdfIn PDF document text
    • http://almar-bus.pl/userfiles/file/zekofasolobekopomubif.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/ed110e4945c85b733bb2cf178e45415a/lenurilizakafuzufe.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c084e635410---68212916173.pdfIn PDF document text
    • http://csc0535.com/userfiles/file/20210614160112_own2a3.pdfIn PDF document text
    • http://divorcefinance.nl/uploads//file/kibekozajirorudedaf.pdfIn PDF document text
    • http://skupka23.ru/upload/m/54445310766.pdfIn PDF document text
    • http://giustizianuova.it/userfiles/file/87105688431.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160cb3fd2e05ff---88215611955.pdfIn PDF document text
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/ms3rmjbdgl0pimh2htvie1h677/xavixaserujovuledobibam.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/4a8071395d447794fdf0335bf1f1f188/todojinepam.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/c13dbc8bb0fdd2e0573980236826099d/84853709007.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606ff93d45e2d---95151785470.pdfIn PDF document text
    • http://huh.hu/UserFiles/File/zozomufuluwifemexixu.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083ab5ac055f---73468913811.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/160bc02d2b203b---fumudela.pdfIn PDF document text
    • https://kawanmto.com/contents//files/31808688799.pdfIn PDF document text
    • http://bikipvuikhoedep.com/app/webroot/files/editor_upload/files/zojisos.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/gezes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=i+was+baptized+as+a+baby+should+i+be+baptized+againPDF 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_off0000e39b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE39B 16660 bytes
SHA-256: de5ce45fe36993ddd3e199c8c1db69cd19700eec26bb29449b356649233632c2
font_01_sfnt_off00010eb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000126d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126D0 11024 bytes
SHA-256: 35a4c556eb59ace592b65e46228cb62d89819d0215c88602610a290d2195e11b