Malicious PDF — malware analysis report

Static analysis result for SHA-256 663a17e3e587fe7e…

MALICIOUS

PDF

68.8 KB Created: 2021-09-25 20:28:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c15cdb06eee7773bfc3b1f38a081a86e SHA-1: 92596108ca2febaad427975630b05eb1ef1e1139 SHA-256: 663a17e3e587fe7e70e1427654d95dedeb4a770b6cccb616a5b8b43e3979fc7a
146 Risk Score

Malware Insights

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

The PDF employs an image-based lure, a common tactic for phishing or malware delivery. It contains numerous external links, many hosted on potentially disposable domains, suggesting a link farm designed to obscure the ultimate destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to redirect users to a malicious site or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9959

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://31kouqiang.com/userfiles/file/1632384520.pdf In PDF document text
    • http://vibratingsieve.com/d/files/96822720505.pdfIn PDF document text
    • http://studioghittigargnano.com/userfiles/files/62565252133.pdfIn PDF document text
    • https://energooptima.hu/upload/File/kuwitukapekajesuronus.pdfIn PDF document text
    • https://client-sms.com/ckfinder/userfiles/files/38798055789.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/44676540778.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/nevelanasarodigabek.pdfIn PDF document text
    • https://vleek.com/uploads/files/35782888071.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/29o1vqof53mjp98qjmptmbtmnc/96684574897.pdfIn PDF document text
    • http://toanlinh.vn/upload/files/8840954462.pdfIn PDF document text
    • http://f-kcc.jp/user_data/userfiles/files/fesipaxuzavesajexalokon.pdfIn PDF document text
    • http://gtlfuelmarine.com/userfiles/file/goniduzikaguwazubaw.pdfIn PDF document text
    • http://stapper.de/sites/default/files/userfilesfile/43896910392.pdfIn PDF document text
    • https://kampusogrenciyurdu.com/file/95483271811.pdfIn PDF document text
    • http://freewest.at/ripikoxotowukemitasaru.pdfIn PDF document text
    • http://rotarytattoomachine.co/project-new/christianbook/upload_images/file/51108078379.pdfIn PDF document text
    • http://lltsg.com/uploadfile/file///2021092007531598.pdfIn PDF document text
    • http://www.veslovani-vsb.cz/soubory/file/86716800095.pdfIn PDF document text
    • https://fetogram.ir/images/upload/files/19615792310.pdfIn PDF document text
    • https://sofanet.ro/ckfinder/userfiles/files/83442237086.pdfIn PDF document text
    • https://oykufestivali.com/ckfinder/userfiles/files/vororajarabisoso.pdfIn PDF document text
    • http://falegnameriacastiglione.it/userfiles/files/24541911864.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/161414a3522925---37183987989.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=watch+the+purge+2013+online+freePDF 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_off0000ad70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD70 14504 bytes
SHA-256: 22454745325a8ba18bb2d99e9ac9f2e5190d34ff28b3e4afa2db717c27d16377
font_01_sfnt_off0000d1ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e9c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9C3 11148 bytes
SHA-256: 6957c86d161489a8fc61c59cdf627944201453bd3df23ff1996d5df19c0a6c18