Malicious PDF — malware analysis report

Static analysis result for SHA-256 84e4fdc5ae4049e1…

MALICIOUS

PDF

73.2 KB Created: 2021-09-09 08:56:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2ca41d7560ac3b8689560709449579be SHA-1: 2abef9fb3812ce2922faad8f1dc61ec5827d5269 SHA-256: 84e4fdc5ae4049e1107d2cf3f13f03bba157c7423abe01be99af1e37cb06eaa6
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm or SEO poisoning attempt. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the structure and URL patterns suggest an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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://coretry.ru/uplcv?utm_term=mobdro+apk+on+firestick PDF link annotation
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/d32453988d7170a966f939b1a1dd5093/zolexafot.pdfIn PDF document text
    • http://duoctruongxuan.vn/userfiles/image/file/lupopuluse.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210907150343.pdfIn PDF document text
    • http://cieplej.pl/imgturysta/file/wenuwewejufida.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/09/files/210903130505.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/161356a93bfb91---dirivutiwolopon.pdfIn PDF document text
    • http://tomaszskiba.com/userfiles/file/wimopasetexepituvibupili.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134d87bef672---78208925484.pdfIn PDF document text
    • http://5lovestartw.com/CKEdit/upload/files/78490268147.pdfIn PDF document text
    • http://www.rannatennis.ee/data/upfiles/files/15377608478.pdfIn PDF document text
    • http://china-miyaco.com/img/file/202192231724.pdfIn PDF document text
    • http://baheth24cars.com/ckfinder/userfiles/files/wodazi.pdfIn PDF document text
    • https://stmarys-perthamboy.com/upload/File/wixejaso.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/mikukoke.pdfIn PDF document text
    • http://sandlnae.com/data/editor/file/xotibisidumafik.pdfIn PDF document text
    • https://larustt.com/upload/ckfinder/files/fekine.pdfIn PDF document text
    • http://crystal-lamp.ru/uploads/files/4901960954.pdfIn PDF document text
    • http://donauwell.at/userfiles/file/bokagazarizexemi.pdfIn PDF document text
    • http://buydecor.ru/uploads/files/36924136593.pdfIn PDF document text
    • http://aexpress.lv/index/images/up/file/79228584164.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/xosiwazaxabalune.pdfIn PDF document text
    • https://bank-kredit.at/ckfinder/userfiles/files/25377704670.pdfIn PDF document text
    • http://denprokhorov.ru/images/file/77230834448.pdfIn PDF document text
    • 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_off0000ba9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA9B 17208 bytes
SHA-256: e1a6bf2c86572d6bc20e8547c76527f6f1f314a13e7b91e4a3df6e34fccdd4c0
font_01_sfnt_off0000e6b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fed0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFED0 10792 bytes
SHA-256: c1d5fa86beb466a7b601aa4a5481ebcd7a0b79a7897a5695e16a704169d233eb