Malicious PDF — malware analysis report

Static analysis result for SHA-256 d578973d6958bddc…

MALICIOUS

PDF

70.3 KB Created: 2021-09-26 08:45:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f918ae7a0c92b58f0c954fc80a5e4b21 SHA-1: 338210efaf24bd3833abc66bd087a7b2c1bb1bfa SHA-256: d578973d6958bddc77354de4c22d8dc55d8576c409fb3c86733d51e172877449
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, many of which are configured as link farms. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using small PDFs on disposable hosting to redirect users, likely to phishing sites or for malware distribution. No scripts were extracted from this sample, but the overall structure and URL distribution strongly suggest a phishing or malware delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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 https://crewmak.ru/uplcv?utm_term=tap+tap+chinese+app+download PDF link annotation
    • http://szkolaprzybranowo.pl/ckfinder/userfiles/files/17415602012.pdfIn PDF document text
    • http://7sate.com/filespath/files/20210925175924.pdfIn PDF document text
    • http://elencostruzioni.it/userfiles/files/solevudibefenus.pdfIn PDF document text
    • http://miass.realxenon.ru/uploads/files/6159095865.pdfIn PDF document text
    • https://svarovanijelinek.cz/ckfinder/userfiles/files/95466584246.pdfIn PDF document text
    • http://moderncarrent.com/user_img/files/raxenamajiromela.pdfIn PDF document text
    • http://internet-trade.eu/UserFiles/file/97590459638.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/202192562346263.pdfIn PDF document text
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/73b9b36d12b2bdbf4b1ae8f6d1d7a875/kifozizoxama.pdfIn PDF document text
    • http://tootingtaxi.com/survey/userfiles/files/53603526917.pdfIn PDF document text
    • https://sunnyrosesschool.com/userfiles/file/wagoxeluw.pdfIn PDF document text
    • http://caythuocdangian.net/images/files/madulugazenij.pdfIn PDF document text
    • http://e-hematologica.pl/users/file/34502246944.pdfIn PDF document text
    • http://reylab.com/userfiles/file/vagibovutizotuge.pdfIn PDF document text
    • http://huseyindurmuslar.com/images_upload/files/xigagarakufubolo.pdfIn PDF document text
    • http://arredamenticucinesiciliane.it/userfiles/files/15187858946.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/diwoladaxokopatozalari.pdfIn PDF document text
    • http://hk-bbc.com/upload/file/xukewosotetizoxodezizapab.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/vofimiropusa.pdfIn PDF document text
    • http://geometrarontani.it/userfiles/files/10785731241.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/16097285794.pdfIn PDF document text
    • https://sofupingame.net/calisma2/files/uploads/93195773797.pdfIn PDF document text
    • https://exam12.menapoint.com/app/webroot/upload/files/sijika.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/4681928376.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/xigoxososaxapujefimo.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_off0000b091.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB091 10560 bytes
SHA-256: c43dc771b1e8bf04ca3331258902b5d46150cf70c5435296dc8dc392ad219e6e
font_01_sfnt_off0000c8ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8AB 16272 bytes
SHA-256: 62ae5056c073604dac8d7eb2ea7930ce27f075f3454410fb7a02ee3c572a3619
font_02_sfnt_off0000f23d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF23D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1