Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c62257c23ef4058…

MALICIOUS

PDF

80.7 KB Created: 2021-09-23 08:43:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7da7247d83393941b3e32c0bb514fc9a SHA-1: e1b104be398a60b189d6635499e8b5f330adac60 SHA-256: 7c62257c23ef405802ffd9dee4ae7072878c76fe6fa5fed50f29d3744b7bd177
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a malformed exploit stream. It contains numerous embedded URLs pointing to external domains, suggesting a phishing or malware distribution attempt. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for multiple links, further supporting a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://oniceh.ru/uplcv?utm_term=talking+tom+candy+run+mod+apk+download PDF link annotation
    • http://chataphan.com/file_media/file_image/file/77393832084.pdfIn PDF document text
    • https://locoffice.ru/userfiles/file/bukepuzim.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/c2nb4bobbs2dtvrvg8a0vicv0n/39132713623.pdfIn PDF document text
    • http://www.bash.cl/media/file/42005378092.pdfIn PDF document text
    • http://banghetretunhien.com/media/ftp/file/pokid.pdfIn PDF document text
    • http://urotunisia.com/uploads/FCK_files/file/pudagaxix.pdfIn PDF document text
    • http://haki.vn/uploads/files/42061696015.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/2021912731249900.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161321da8ad7ac---35925950987.pdfIn PDF document text
    • http://thanhcongtechtra.com/upload/files/11377794463.pdfIn PDF document text
    • https://braus.uz/images/shared/file/85058007724.pdfIn PDF document text
    • https://eletvital.hu/uploads/files/42797706073.pdfIn PDF document text
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/senajubegepoxusebelepur.pdfIn PDF document text
    • http://fxmeat.com/upload/file/3ea1f914a122d7d03aefe6bbf4c896e5.pdfIn PDF document text
    • http://homeopathyhongkong.cn/files/76227988746.pdfIn PDF document text
    • https://shoppingplanet.cityplanet.ro/ckfinder/userfiles/files/48104868596.pdfIn PDF document text
    • http://ecole.ru/text/images/file/sikomavefetamevekukam.pdfIn PDF document text
    • https://ngonluathan.com/images/ckeditor/files/23517356191.pdfIn PDF document text
    • http://fishngrill.iorderfoods.com/uploads/files/34737846782.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/riwamak.pdfIn PDF document text
    • http://geteffective.biz/uploadfiles/file/84713892912.pdfIn PDF document text
    • http://cokhiminhhien.com/media/ftp/file/numafo.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/kivule.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_off0000d62d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD62D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3F 16944 bytes
SHA-256: 66eb83aebfbb9217b62fd00677dbb92c3fa8870b55a8c918a3668a0789c83f79
font_02_sfnt_off00011a17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A17 10912 bytes
SHA-256: 9fdc6a014d4415513b5dfb92f2036aa2c8d53d3f0fa705e9f2342959d50eacd6