Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea7aaf7045018c24…

MALICIOUS

PDF

80.5 KB Created: 2021-09-11 18:24:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5d1b40b182c7e8e21bdafea71aacf756 SHA-1: 45c8dfe1d8eb2e5c8a371f8d3cdf51247d8541ac SHA-256: ea7aaf7045018c249c812031301cb0074ecbb16515889bd454852bab761c9e0b
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains malformed streams and is flagged by ML classifiers and ClamAV as malicious. It includes numerous embedded URLs, many of which point to disposable domains and appear to be part of a link farm, suggesting a phishing or credential harvesting attempt. The presence of external URIs and the overall structure indicate an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://teamwork-poetschke.com/ckfinder/userfiles/files/dikipiw.pdf In PDF document text
    • https://pachetedeturism.ro/images/files/labafaxalej.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/pesedifajikumux.pdfIn PDF document text
    • http://lifecontinues.ru/images/files/nudoboja.pdfIn PDF document text
    • https://miet.hu/kepek/23212967922.pdfIn PDF document text
    • http://petraifevronii.ru/ckfinder/userfiles/files/73985195878.pdfIn PDF document text
    • https://tunhuaduytan.com/upload/userfiles/files/98829898583.pdfIn PDF document text
    • http://indago-rovigo.it/userfiles/files/raxinejur.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/98354109325.pdfIn PDF document text
    • http://farmaciafici.com/userfiles/files/90136706616.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210909111149.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/lidetud.pdfIn PDF document text
    • http://debten.net/UserFiles/File/kafik.pdfIn PDF document text
    • http://my-hustle.net/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/63103975871.pdfIn PDF document text
    • https://lyonsinn.com/nbloom/fckuploads/file/mujubelix.pdfIn PDF document text
    • http://cokhilegia.com/upload/files/55257459436.pdfIn PDF document text
    • https://simpangkanan.com/contents/files/10042492977.pdfIn PDF document text
    • http://www.koeru.eu/failid/file/joxopasipexapi.pdfIn PDF document text
    • http://aci-immobilier-douai.fr/userfiles/files/21924463394.pdfIn PDF document text
    • https://immsac.pe/sgi_userfiles/userfiles/files/64865073069.pdfIn PDF document text
    • http://nwatchonline.com/userfiles/file/32581210382.pdfIn PDF document text
    • http://bevillelecomte.ovh/ckfinder/userfiles/files/64644009290.pdfIn PDF document text
    • http://master-stroi76.ru/userfiles/file/65116608139.pdfIn PDF document text
    • http://galaxyjewel.cn/uploadfile/files/zekalad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=can+u+download+itunes+on+androidPDF 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_off0000d6cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6CF 10456 bytes
SHA-256: 3f99ebc77a5cf200f0b4595756739ef45afbb9e5eb977c3dc859cfae32a95125
font_01_sfnt_off0000eebf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000106d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D1 17636 bytes
SHA-256: 314ddeb19c0dcaa79ebd49a326076dda581dd387c43cbaaaae465851ca16b93a