Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6d88620f195ec87…

MALICIOUS

PDF

88.4 KB Created: 2021-06-30 09:18:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a20fa1b69d86035b0ac6d3ccb05f938 SHA-1: b18962d90f9a8da5b61c9d3767904fbe003792c0 SHA-256: b6d88620f195ec874c3e543e823111177cf724c1b91934b2599615a324a38269
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, many of which appear to be compromised WordPress upload directories. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true malicious intent. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 http://igabana.com/upfolder/e/files/20210623213016.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a17b096d827---85895439873.pdf
    • http://firmen-bekleidung.at/userfiles/file/49061437684.pdf
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6747978a6---kosogixufalajusodavo.pdf
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/c4ddeebf2605d61ac43ddacfec6aa05b/85644323186.pdf
    • http://tubietelbar.hu/uploadfile/50521317230.pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c1fe114de07---rixedadasikivatosoriw.pdf
    • http://cokhixnktientien.com/Images_upload/files/67464894931.pdf
    • http://krzeptowski.pl/file/mogifebigimulena.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160965656547d7---17981860765.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a182a13bd---35567796992.pdf
    • http://taiyoaquris.cn/upload/userfiles/files/20210617184906.pdf
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/dd7ef25a0fa3f429a4559a7889fad868/57758222191.pdf
    • https://badrivishal.com/media/13663332511.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607899c2d2373---97768518857.pdf
    • http://www.knickmeier.net/images/pageimg/file/wusozijisegurunovepevup.pdf
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/5d92a827c3759d1e69658debaaf15aa7/45610894382.pdf
    • http://mhfmjournal.com/data/22/2/55/64/2544879/user/2788947/htdocs/userfiles/file/kupufevawa.pdf
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/8631028d42ae5f7ae4246191b759c6c1/62243151339.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-5-7/20210507124626774764.pdf
    • http://chickenwild.com/upload/contents/images/images/vofim.pdf
    • http://castudio.eu/userfiles/files/mowupogetamexizob.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7fb708ca7---68428991738.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=the+mediterranean+region+are+characterized+by+heavy+rain+in
    • 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_off0000f435.bin
3fdfa2153fcc48ac7875e460b45679d14c2d381a7e14cec4ba620174376ae434
pdf-font-stream PDF embedded font (sfnt) at offset 0xF435 10944 bytes
font_01_sfnt_off00010d38.bin
2e48b69a7dab92ab3ab32b468ddbaedaadfe1752074f5c38a6c2559d8445c9d2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D38 18652 bytes
font_02_sfnt_off00013bde.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BDE 16792 bytes