Malicious PDF — malware analysis report

Static analysis result for SHA-256 1099c76b864e0c67…

MALICIOUS

PDF

82.4 KB Created: 2021-09-08 02:11:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b3b8f6ebc4a247e3bf43a0e1d9841bc5 SHA-1: cd541c81a755f6cd6446bd706f8347f81ee5b67e SHA-256: 1099c76b864e0c67ad8cd77a6c00f37121b98e57a054ed86e8f2352bd2783e38
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It functions as a link farm, containing numerous URLs that point to various websites, many of which appear to be compromised or disposable hosting. The primary purpose seems to be directing users to external sites, likely for phishing or to download further malicious content.

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://drafthe.ru/uplcv?utm_term=punctuation+worksheets+grade+8+pdf
    • http://tragiaocolamsapa.com/userfiles/image/file/35213249743.pdf
    • https://gionggiacam.com/ckfinder/userfiles/files/kejokajuzosasubafizof.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610baa6603a85---87905140049.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b5fe403915c---65870809784.pdf
    • http://nabisori.com/userfiles/file/23986466223.pdf
    • http://abwingsde.com/uploads/files/rezesudopuwonomanigutep.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/e8487a92bc0c80a301344dafcf394907/5785503747.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607db5384863d---wogugajuxowolevi.pdf
    • http://slenderclub.cz/ckfinder/userfiles/files/53291390667.pdf
    • http://whitedwarf.ru/public/images/ckfinder/files/dotox.pdf
    • http://carneslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/16864569744.pdf
    • http://pololanna.com/user_img/files/29411027257.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134642f14231---82141387633.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f0ec58acf---11226077355.pdf
    • http://chinatriage.com/ckfinder/userfiles/files/34708791160.pdf
    • http://doktor-okonski.pl/uploadimg/file/vujomim.pdf
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/kg943803trqkup032v5sok426e/60081348630.pdf
    • http://kme-kme.cz/files/file/poladujam.pdf
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcfd7a6f259---11185418003.pdf
    • http://mextro.de/upload/files/82921294232.pdf
    • http://thaihotelsale.com/FileData/ckfinder/files/20210809_008424CE1C813643.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe2680b825---37246026414.pdf
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/fatavaruvewapotodamale.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dab5.bin
319f3baa146076f253209913abcce881812ee99843ce437633a4fee811782689
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAB5 11340 bytes
font_01_sfnt_off0000f549.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF549 16792 bytes
font_02_sfnt_off00010d5b.bin
0c2abfe9672860624cef858684a74ea99616d1d9396874a63052ed70b3857462
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D5B 17972 bytes