Malicious PDF — malware analysis report

Static analysis result for SHA-256 acc81a92e60468dd…

MALICIOUS

PDF

82.8 KB Created: 2021-09-17 04:53:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cbcadd5b196fe094f1cd31b1aed3937a SHA-1: 0a9841c81a7a3e28a23ed6c464d0d08f7b5c1618 SHA-256: acc81a92e60468ddb581daeae18c7ed9b497e372fe22e5fc9fed59ddd4f3f551
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically points to the document acting as a link farm, directing users to numerous distinct hosts. While no scripts were extracted, the structure and heuristics suggest the PDF is designed to redirect users to potentially malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://avesta-hmora.boj.se/uploads/userfiles/files/27629831298.pdf In PDF document text
    • http://sovaimm.it/userfiles/files/lekepubiwi.pdfIn PDF document text
    • http://www.ks-klinika.ru/ckfinder/userfiles/files/juluporaj.pdfIn PDF document text
    • http://hoya-system.com/uploads/files/202109131423596447.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/c28eqe1etj99jotuqi2ruuc5g2/42941407576.pdfIn PDF document text
    • http://vhktn.at/images/content/files/83792425429.pdfIn PDF document text
    • http://immodraft.nrw/images/architekten_agentur_images_/file/94824655465.pdfIn PDF document text
    • http://fsnmmaterials.com/UPFILE/userfiles/files/73170121580.pdfIn PDF document text
    • http://hzqljsj.com/images/upload/File/sovefexakuginu.pdfIn PDF document text
    • https://nicklason.se/ckfinder/userfiles/files/zokakitugowetuwajusoxofof.pdfIn PDF document text
    • http://engroupe.ca/aym_image/files/tatodugujesa.pdfIn PDF document text
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/kawetolimedabarawawa.pdfIn PDF document text
    • https://kolkatanagariksammelan.org/ckfinder/userfiles/files/fozanag.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/86168137756.pdfIn PDF document text
    • https://braindevelopmentmaps-org.neurondevelopment.org/userfiles/files/gopemujurumo.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/zorafon.pdfIn PDF document text
    • http://maryalo.com/userData/board/file/forajipikosetefafonobaf.pdfIn PDF document text
    • https://cfi-registration.org/buzzboxgift/img/userfiles/files/4046015108.pdfIn PDF document text
    • http://kawoka.com/userfiles/file/jexomosif.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614018fa200d1---desotizi.pdfIn PDF document text
    • http://yilbasipromosyonu.com/userfiles/file/tapisujunanizixidesirap.pdfIn PDF document text
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/73955745673.pdfIn PDF document text
    • http://datev.hu/ckfinder/userfiles/files/10727064313.pdfIn PDF document text
    • https://studiovizia.com/webroot/img/content/files/98460840618.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=caring+words+that+start+with+yPDF link annotation
    • 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_off0000dfa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f7b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B3 17872 bytes
SHA-256: 570d84b6392d39fe94583e164fd1a355c75f029abbb03987e67d9e9241350b3b
font_02_sfnt_off000125ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125CA 10580 bytes
SHA-256: f96e69c84923b4267ff22c42dd6c28652a393407c42d60e087fdecc4a2a4934d