Malicious PDF — malware analysis report

Static analysis result for SHA-256 36f9f4c1f935fe4f…

MALICIOUS

PDF

97.4 KB Created: 2021-09-15 06:27:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: eda17b9b1577180a775918e030061312 SHA-1: 87daa3e2ea5c8a25233b7dcfbdd5d8f9719b2f90 SHA-256: 36f9f4c1f935fe4fb50d0762e0215954c2c3e06f685dbeab8e86b63e943ee0be
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. The presence of numerous URLs, including those with UTM parameters, suggests an attempt to lure users to potentially malicious or phishing websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://crewmak.ru/uplcv?utm_term=cake+web+browser+apk PDF link annotation
    • https://hotelindigha.com/FCKeditor/file/71197180744.pdfIn PDF document text
    • https://maria-galland.ru/files/file/kanibenedavomenod.pdfIn PDF document text
    • http://motivationandmomentum.net/ci/userfiles/files/36762909767.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/161413d06372c6---firosifegefumigufupiteped.pdfIn PDF document text
    • http://www.childofafrica.org/media/userfiles/file/85675646422.pdfIn PDF document text
    • https://pokereshop.cz/data/file/papututeretalasipew.pdfIn PDF document text
    • https://activepymes.com/pub/file/dukubagamiw.pdfIn PDF document text
    • http://partnerplus30.ru/images/fornews/files/kopenowasenawopakuzodibaf.pdfIn PDF document text
    • https://dorfadvertising.com/ckfinder/userfiles/files/pimanukalolejefod.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/13266895889.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16139f64530c5b---9613799606.pdfIn PDF document text
    • https://u15.ch/ckfinder/userfiles/files/wuwegur.pdfIn PDF document text
    • http://tantex.org/tantex/tantexuserfiles/file/rajoduzanemojej.pdfIn PDF document text
    • http://altiro.nl/home/tjerk/file/62757574456.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/16338e24d9b7631b771ee9cbbcd311df/xesozigud.pdfIn PDF document text
    • https://www.totalblissbeauty.com.au/application/third_party/ckfinder/userfiles/files/80087908618.pdfIn PDF document text
    • http://ctcinsulator.com/uploads/file/39852593432.pdfIn PDF document text
    • http://gestaocipa.com/public_html/Imagens/file/fotepijud.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/73677470568.pdfIn PDF document text
    • http://epilia.com/upload/FCKEditorfile/13235853467.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f94c0c25e8---nasogiravexulo.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/85340656525.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_off0001153a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1153A 19944 bytes
SHA-256: cc89bc853d07151a44fa02887a94529e5f227c30599d46d4346df4f6ca1b494b
font_01_sfnt_off00014964.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14964 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001617b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1617B 10256 bytes
SHA-256: 6d1b417a9b44df1a54ed7d9983cd82d6798ebe2e1d71b099c856cc772f7b3e2e