Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6cdea3088539778…

MALICIOUS

PDF

71.0 KB Created: 2021-09-28 01:26:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 773adcb09c6159ea956238ab9e2ee159 SHA-1: b0e3ddefb4017a5243e4ddad61482ad7dcdb5608 SHA-256: f6cdea3088539778946ffa8a8e9864839d7445c96dcb01e5d3bd81f2c75c15d0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to various domains, suggesting it functions as a link farm. One heuristic specifically identifies it as a 'non-clustered link farm on disposable hosting', reinforcing the phishing or malware distribution vector. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://queure.ru/uplcv?utm_term=how+to+remove+a+safe+mode+on+phone PDF link annotation
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/muniboporim.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/a2191a4df3714890104b7e41b5c49b5c/liwalogi.pdfIn PDF document text
    • http://xn--4k0b43gkwo4gn.com/upload/editor/file/11888827802.pdfIn PDF document text
    • http://valentine.tutaylamhet.com/storage/ckfinder/files/dosetenumejemumawobuz.pdfIn PDF document text
    • https://trexanh.net/upload/files/podilonumujut.pdfIn PDF document text
    • http://tehpromyar.ru/media/file/vemekujavuginunavixanid.pdfIn PDF document text
    • https://kirmatas.com/userfiles/file/zixavurej.pdfIn PDF document text
    • https://carsen.sk/editor_uploads/system/files/64576507605.pdfIn PDF document text
    • https://srmhomes.com/images/bulk_images/files/49007110579.pdfIn PDF document text
    • http://www.asap-recruitment.net/upload/file/65850330143.pdfIn PDF document text
    • http://eko-uklid.com/files/file/3603831759.pdfIn PDF document text
    • https://yauspeshen.com/ckfinder/userfiles/files/72093203474.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/20289831521.pdfIn PDF document text
    • http://printrun.nl/userfiles/files/42314561767.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/vivawewosubulitivuw.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/96617629032.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc3af68713---3300210907.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/nutosawifowosemisebemon.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1631881388.pdfIn PDF document text
    • http://boletos.luzservicos.com/ckfinder/userfiles/files/basafewofinuke.pdfIn PDF document text
    • http://cssh.es/img/file/getanoxijufejo.pdfIn PDF document text
    • http://sellmysayarah.com/userfiles/files/bapamenuvokigew.pdfIn PDF document text
    • http://cornaredo.gattinonimondodivacanze.it/themes/userfiles/files/8590322533.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/jukebasemunidolikinimob.pdfIn PDF document text
    • http://sinoscaform.com/upload/ckimg/files/202109060903051673.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/29583293773.pdfIn PDF document text
    • http://www.alexgis.com/siteuploads/editorimg/file/sifomeluwiduzokiv.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_off0000b3f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3F7 16404 bytes
SHA-256: e44f58324169d8a13f74b101eac22184d2ef20efd0a1b471ee186809af35ed3b
font_01_sfnt_off0000ddb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C7 10768 bytes
SHA-256: d9ac47296926647ccd44be553575dccf9f46a5ced41b19bfe9bc58c3742b4684