Malicious PDF — malware analysis report

Static analysis result for SHA-256 7621c88b6ac36de8…

MALICIOUS

PDF

81.8 KB Created: 2021-09-10 15:35:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e163a1b8353f2c9780d7f1cf4ee620ed SHA-1: 40188124fe150a2d14419fa512a96f8e22022495 SHA-256: 7621c88b6ac36de8563b92c9e2dc357bb2bcad27b8abbb9c926ae5d8dd004dc9
134 Risk Score

Malware Insights

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

The PDF contains a high number of embedded links pointing to various domains, many of which are likely disposable hosting. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic and the presence of a 'Download Now' lure suggest a phishing or scam attempt. ClamAV also detected this file as 'Pdf.Phishing.Trojan'. The primary IOC is the URL associated with the link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613acf770e6dd---25730555863.pdf In PDF document text
    • http://datong-travel.tw/upload/ckeditor/files/20210910153444.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/c59ccb55bbe388d8e2593faa434c978d/58964354315.pdfIn PDF document text
    • https://alkoplast.rs/files/nenimuwijupeluwupifawarad.pdfIn PDF document text
    • https://history.tlshaa.org.tw/ckfinder/userfiles/files/vafotobitopusojute.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/peniliwewewewojufemunile.pdfIn PDF document text
    • http://www.neoneophytou.com/ckfinder/userfiles/files/wejukizenukeja.pdfIn PDF document text
    • http://ky-auto.com/uploadfile/files/91066996690.pdfIn PDF document text
    • http://taociren.com/upload/file/21091010023535162636pz57dgebyt.pdfIn PDF document text
    • http://parbatsamajjapan.com/img/files/files/wixevutomerogelaror.pdfIn PDF document text
    • https://gulamanis.com/contents/files/rugufopifotime.pdfIn PDF document text
    • http://vanhacollection.com/images/files/94876652608.pdfIn PDF document text
    • http://101balkon.ru/upload/files/81966009979.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/41416590664.pdfIn PDF document text
    • https://solturism.ro/images/file/24762125735.pdfIn PDF document text
    • http://barexkft.hu/userfiles/file/kogaguxebazew.pdfIn PDF document text
    • https://thebillionbottom.com/business_school/uploads/file/fugug.pdfIn PDF document text
    • https://flcevent.fcu.edu.tw/plugin/ce1/ckfinder/userfiles/files/20210908171708.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/71527092056.pdfIn PDF document text
    • http://wakabaeducation.com/userfiles/file/81008621938.pdfIn PDF document text
    • http://autowagon.it/userfiles/files/62472348003.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/68164271552.pdfIn PDF document text
    • http://dreiseengrundschule.de/files/wefonanen.pdfIn PDF document text
    • http://coolscape.info/images/files/35806729819.pdfIn PDF document text
    • http://fecoil.com/userfiles/file/2653720088.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=android+emulator+macbook+proPDF 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_off0000db9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB9B 10820 bytes
SHA-256: 6cff33e2924d0c1f45812e3bed19cf65e8927dffe5d8b72407e65ab211838705
font_01_sfnt_off0000f451.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF451 17572 bytes
SHA-256: c64929c2598837a48d3f4eff31ca6e2c859bea1d93b1d12573373d03075943f5
font_02_sfnt_off000121d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1