Malicious PDF — malware analysis report

Static analysis result for SHA-256 d42eb4ab73c33fc9…

MALICIOUS

PDF

79.0 KB Created: 2021-05-18 01:04:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: f77716aedce470ad9cc6c3b9611872b8 SHA-1: 36a17c5784f44d20ed43e0c21705b683b35517a5 SHA-256: d42eb4ab73c33fc999cccb1287ed9021c8ed181fc6b561f107886c5ab2556341
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. This structure is indicative of a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly support the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9771

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://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160714a3848e31---75974966763.pdf In PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/86231bb8ab6d80ae7ae054630873a9e4/lovafoku.pdfIn PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/984b26558f469572d33a88cf237e297f/50753146039.pdfIn PDF document text
    • http://alpha-cp.com/userfiles/file/67966659580.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/97p893f9mogqj3hvh7a45387f7/sifaxa.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/sjgvvpcpudj05gdonrd7q1k47n/remaxexuvaxatojiwi.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/98168437609.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160780108bd282---xoxugabekujowinidanotud.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/sawopesokolazami.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/mht4of1ve84h1164sj0nplhinj/fomoladav.pdfIn PDF document text
    • http://aucoindeshalles.com/menu/file/27575737812.pdfIn PDF document text
    • https://evenimentecastel.ro/wp-content/plugins/super-forms/uploads/php/files/9ijbjt4n2i2g6gga6hjiji0482/wisivavasagekawi.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/29k1vbn817bv6ga3kcm8q379p5/pivawulut.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a1d1e47d289---kisinixuz.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160817d765662a---sugepozapakilu.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/db539ed871fb3897032b76299c131d60/6814324328.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160851be683569---zeweriwuduwaxu.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/72a06e20b2517dd9a040c6da85730b47/pisedesuluwujuv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=ebob+ekok+sorular%25C4%25B1+8.+s%25C4%25B1n%25C4%25B1f+pdf+100+soruPDF link annotation
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED95 5400 bytes
SHA-256: 462256f61430754302c1d5dcc1fa589db3530effe4d9d4bcdcc9a5c0c5bfc480
font_01_sfnt_off0000fffa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFFA 11984 bytes
SHA-256: 5a7da3818666db30317296134e93552ace19ccb401949d50f819db2a5c5ff6e6
font_02_sfnt_off00012668.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12668 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c