Malicious PDF — malware analysis report

Static analysis result for SHA-256 5476818bc71dbe88…

MALICIOUS

PDF

90.6 KB Created: 2021-09-19 18:03:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a19b8bb5902df3027b3f9036c49186ac SHA-1: 365659d636c9ffdc274153e5d79b351ef5e71fa7 SHA-256: 5476818bc71dbe8863dfe7264f2c6b9fe6fd885a0855969ba86d41415089a353
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal embedded JavaScript and a link farm pointing to compromised WordPress uploads and other disposable hosting sites. The embedded JavaScript likely serves to facilitate the download or execution of further malicious payloads, while the link farm aims to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=jailbreak+android+free PDF link annotation
    • https://hv2barrier.com/application/third_party/ckfinder/userfiles/files/99697815482.pdfIn PDF document text
    • http://roomyab.ir/basefile/roomyabir/files/xetizoxoseretititapugi.pdfIn PDF document text
    • http://pm-ural.com/uploads/files/91788518804.pdfIn PDF document text
    • http://hoaisonland.vn/upload/files/55938102287.pdfIn PDF document text
    • http://ballmillfactory.com/d/files/92580586015.pdfIn PDF document text
    • https://pakianco.ir/data/image/uploads/news/files/favegawevitak.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/34545006229.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/78671312477.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/10610314449.pdfIn PDF document text
    • https://tsegypt.com/file/netibisufidodomuwomex.pdfIn PDF document text
    • http://closehorses.com/userfiles/file/85579330084.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/momotodepuwatatoziz.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/95512401979.pdfIn PDF document text
    • http://rialta.ie/userfiles/files/gozewobuzorogiligojag.pdfIn PDF document text
    • http://h-n-s.net/userfiles/file/lunubilel.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613af6a7ce199---toponamufemawibojuxevupol.pdfIn PDF document text
    • https://tiguan-wiki.ru/file/vebipezujafanujakew.pdfIn PDF document text
    • https://marmetal.cevhertemizlik.com/userfiles/files/jedazalirovuj.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/a960e30477f88541422c2bb5883817c1/61945020992.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133648831957---51216530820.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff62ced44c---41973125566.pdfIn PDF document text
    • https://jvlegacyhomerepairsmd.com/nbloom/fckuploads/file/82290825057.pdfIn PDF document text
    • https://ms1oke.com/contents/files/50583763248.pdfIn PDF document text
    • http://sriraghavendratemple.com/ckfinder/userfiles/files/pijadowe.pdfIn PDF document text
    • https://www.tulsarad.com/my_content/js/ckfinder/userfiles/files/1074843012.pdfIn PDF document text
    • http://www.nachtruhe.info/up/files/xulosumaxogev.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_off0000ffda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000117ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117EC 17664 bytes
SHA-256: b7a9e5c7bf28f089212b7aceb88ed7376eedd80760201a24f64aaddae9c07448
font_02_sfnt_off000145d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145D4 10304 bytes
SHA-256: a118fcb477ac83ab3b70eac396acf6e8daa44b63a850c1983ea35c21d14fff6e