Malicious PDF — malware analysis report

Static analysis result for SHA-256 90920d6f87a5e179…

MALICIOUS

PDF

84.2 KB Created: 2021-09-17 15:57:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b262d529042fcda89c96dd5db3335271 SHA-1: bc6174877ba0ac70a7fd6497ae54bfe0ff666af9 SHA-256: 90920d6f87a5e179bb30962575b3dc38149c18286ad001369f45a02e913dfd4b
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various domains, many of which appear to be part of a link farm designed to redirect users to potentially malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, further suggesting malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://crewmak.ru/uplcv?utm_term=android+telefonda+yedekleme+nas%C4%B1l+yap%C4%B1l%C4%B1r PDF link annotation
    • https://albawadiroad.com/userfiles/files/81551410153.pdfIn PDF document text
    • http://barefoot.pl/userfiles/file/91790422021.pdfIn PDF document text
    • http://fundacionecla.org/resources/original/file/41168892222.pdfIn PDF document text
    • http://www.gabrielamaciel.net/images/content/file/65754121038.pdfIn PDF document text
    • https://virtrade.gr/userfiles_lybo/file/88008962511.pdfIn PDF document text
    • https://elitstroycraft.ru/source/file/pobuxodituwabojoxusugidab.pdfIn PDF document text
    • https://semagro-msw.ru/pics/images/file/lisusegiguforuti.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/5gu7h8jr8iptbhermoena04pt4/refisepanodumonufobesetun.pdfIn PDF document text
    • http://infinity8talents.com/userfiles/file/wizixajabosuw.pdfIn PDF document text
    • http://theofficeplus.com/userfiles/file/84948638846.pdfIn PDF document text
    • http://art-ball.net/files/file/woxuwadunideruxes.pdfIn PDF document text
    • https://flims.atelierleuthold.ch/userfiles/files/wawidodunojebejuxusoxom.pdfIn PDF document text
    • https://megashina24.ru/files/files/62975860741.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/c4b6cbc094290f11a1738d794a36fa6b/96012823363.pdfIn PDF document text
    • http://chaitraglaze.com/uploads/zojowixovunafirizukiwu.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/62586086658.pdfIn PDF document text
    • https://cuatudongsaigon.net/uploads/files/79797690715.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/17256610168.pdfIn PDF document text
    • https://fullmagicweekend.com/ckfinder/userfiles/files/nokunesupe.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/tonasizeraninukagetip.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/19517819827.pdfIn PDF document text
    • http://mywymc.com/userfiles/file/43101189400.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16131656daf037---19268241722.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e9955e02ba---75211731354.pdfIn PDF document text
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/94062558367.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_off0000e0a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B8 18900 bytes
SHA-256: ae7b027264d94d4ead25880dc4239522d1cb4ff9e9bf4fb3a457633222556bbb
font_02_sfnt_off00012774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12774 10892 bytes
SHA-256: 8db1940f98fbe2a4601aafe45f1f2d7f3ed03a020bb472b4ae7099f36efffb7e