Malicious PDF — malware analysis report

Static analysis result for SHA-256 55dd881a015c394c…

MALICIOUS

PDF

92.4 KB Created: 2021-09-24 06:46:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: ab2ec2a98329d7e88b8f9d19326de4ed SHA-1: e85e94fe5978b4131cbbec7abe9bba8213c16fcd SHA-256: 55dd881a015c394c3b6966de06dffa8660638fc12f3e2b7c6da829de647173d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of external URI heuristics and link farm indicators confirms the document's purpose is to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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
  • 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://synerhu.ru/uplcv?utm_term=boboiboy+all+games PDF link annotation
    • https://kuwaitpolyurethane.com/ckfinder/userfiles/files/32302768087.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/bolujokobanejapulavodozut.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/a4bed8d855df4176adf335a9d2ffbc39/wejuxur.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/64blttq7l9ak8s2s54p8euhff2/govoxopigodisivopokomine.pdfIn PDF document text
    • http://tulga.ru/editor/files/taxobitupevomejuxowagu.pdfIn PDF document text
    • http://songdolandmarkcity.com/userfiles/file/23710622488.pdfIn PDF document text
    • http://xmzs.org/userfiles/file/51973104331.pdfIn PDF document text
    • http://labradory.pl/file/mufakegojasemikiwagu.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ecb4793ce5---xakazilegasex.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142efafedaaf---xerok.pdfIn PDF document text
    • http://ordineveterinarivenezia.eu/userfiles/files/55094072116.pdfIn PDF document text
    • https://wotfiles.com/ckfinder/userfiles/files/lizutigeregabisifiwuta.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/24838841952.pdfIn PDF document text
    • http://ramenhajimetustin.com/uploads/files/ruwuvalapefutun.pdfIn PDF document text
    • https://anesaportugal.org/upload/file/fanumumugagiwepux.pdfIn PDF document text
    • http://mcutech.net/files/jutimexilopabapipevisuzug.pdfIn PDF document text
    • http://uptindia.com/newsimages/file///16914834021.pdfIn PDF document text
    • http://lachambredechos.com/userfiles/file/4581781866.pdfIn PDF document text
    • http://tsraccountants.nl/mailing/images/photo/file/52092486553.pdfIn PDF document text
    • http://barefoot.pl/userfiles/file/fekenowi.pdfIn PDF document text
    • http://merrygoldholidays.com/ckfinder/userfiles/files/lodor.pdfIn PDF document text
    • https://fajanav.com/aym_image/files/lonujefesupasuretusu.pdfIn PDF document text
    • http://kolaykanal.com/userfiles/files/vukenilotujinani.pdfIn PDF document text
    • http://belly.bpv.su/content/files/files/3211018964.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_off00010327.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10327 18776 bytes
SHA-256: 683e4d6bb9d11ef9ea53c9ca15845b84d0a95c113c77b5299bcb7d5ded4f03e1
font_01_sfnt_off00013464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13464 10456 bytes
SHA-256: 0a240e5be090ae9e41dc21fdf060fa34e64ba9b18711e14f5303ee0c532ed2f7
font_02_sfnt_off00014c39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1