Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d85821163e8a02e…

MALICIOUS

PDF

81.2 KB Created: 2021-09-12 11:54:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1ec728d46514e3cf09037003f408a4dc SHA-1: f67497593b174c5304569841f220975544ab3930 SHA-256: 1d85821163e8a02eadf035c25d2128df5775f3c8f2c54e2f6ceda5a2ac2a8d7e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, suggesting a link farm designed to obscure the ultimate destination. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a pattern of using disposable hosting for these links. While no scripts were explicitly extracted, the ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://idcla.net/upload/files/18536618292.pdf In PDF document text
    • http://czechnews.cz/userfiles/files/sigogidatal.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/161302f9602c1b---rerixopegepaxevasev.pdfIn PDF document text
    • https://dusunceokulu.net/resimler/files/79804073565.pdfIn PDF document text
    • http://altadirezione-consulting.it/userfiles/files/pazurore.pdfIn PDF document text
    • https://manuscripthandler.com/userfiles/file/surigamirogafitovusug.pdfIn PDF document text
    • http://iuf.kr/pds_down/files/komipibimumuzedate.pdfIn PDF document text
    • https://callmarkinvestments.fortunekenya.com/callmark/files/59278564373.pdfIn PDF document text
    • http://rsentco.com/upload/file/vunakub.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/bamefekug.pdfIn PDF document text
    • https://pachetedeturism.ro/images/files/kopokifejijizebiv.pdfIn PDF document text
    • http://cosmik-kinoteatr.ru/sadm_files/22437064555.pdfIn PDF document text
    • http://mavelikaradiocese.org/rapha/ckfinder/userfiles/files/davopamugiviv.pdfIn PDF document text
    • https://yocarbroker.com/upload/ckfinder/files/fodujotasijutesonomisuxi.pdfIn PDF document text
    • https://horgaszvelem.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/87696630626.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/jokixegul.pdfIn PDF document text
    • http://www.anieliasfx.com/uploads/textareas/file/nefozexevidurinoziti.pdfIn PDF document text
    • https://anpheatingandac.com/nbloom/fckuploads/file/48167531311.pdfIn PDF document text
    • http://cementfeet.com/userfiles/file/xetuziwawa.pdfIn PDF document text
    • http://kabaretyimpresariat.pl/Upload/file/91220896238.pdfIn PDF document text
    • http://jhdljz.com/userfiles/file/1631029729.pdfIn PDF document text
    • http://csa.china-led.net/static/editor/ckeditor/ckfinder/upfile/files/59449771794.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/43458920773.pdfIn PDF document text
    • http://weiddy.com/uploads/files/202109121649173004.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=things+from+letter+vPDF 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_off0000d942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD942 10528 bytes
SHA-256: 492a0a25e6d267bb0f1456fc9b21d81832a306a579b052e0165428c745291e0d
font_01_sfnt_off0000f108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF108 17880 bytes
SHA-256: 21711a8afc5a21998fa5e02291d581f1d3803e8e192021489cc0a30f6619084d
font_02_sfnt_off00011f1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1