Malicious PDF — malware analysis report

Static analysis result for SHA-256 21104132369e05ae…

MALICIOUS

PDF

80.6 KB Created: 2021-10-11 12:33:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 76f1863fc2807aac3da4558f92974516 SHA-1: 31954b0fc60f82b3d0b9a471cae62e9b7f9a5492 SHA-256: 21104132369e05aeafb40965032cfbe579f2bd1b4eb964056f71c7849d0b7422
156 Risk Score

Malware Insights

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

The PDF contains a link farm, with many URLs pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple compromised CMS upload links suggests an attempt to host malicious content or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/f0bfdca0a608798908112696416274a3/nolekola.pdf In PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/94b62845c750c4850828ebc55a4dbc60/wozefaviporid.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16134556d2d848---kizufe.pdfIn PDF document text
    • http://synfarm.com/upload/files/34502945022.pdfIn PDF document text
    • http://palletgoanloi.com/img-dn/files/5943156077.pdfIn PDF document text
    • http://omatsuri.kr/data/userfiles/files/93535445141.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/miwulakifugokopijolu.pdfIn PDF document text
    • http://decom.pro/admin/ckfinder/userfiles/files/somitujudanurapemofixewo.pdfIn PDF document text
    • https://royal-art.pl/uploads/userfiles/files/melowajo.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/93361584976.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/e3j71ipj8fqn6foagf7h9ddsod/8400775980.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/61570243142.pdfIn PDF document text
    • https://aarushimukhwas.idealviews.com/userfiles/files/70441442307.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/83446236621.pdfIn PDF document text
    • https://misbahelmudii.org/ckfinder/userfiles/files/nemupoluteboruvefagiwogi.pdfIn PDF document text
    • http://www.santamyoga.be/images/file/jilusonaxojaxukopajadir.pdfIn PDF document text
    • http://huemin.com/fckeditor/userfiles/file/foparovonoropomupivivetu.pdfIn PDF document text
    • http://sanjarbek.uz/userfiles/file/26389157183.pdfIn PDF document text
    • http://morpheus-architects.com/file_media/file_image/file/lexoxek.pdfIn PDF document text
    • http://gwtcs.org/Content/uploads/files/sewizuzakerunanidi.pdfIn PDF document text
    • http://rlangkhan.com/upload/userfiles/files/75179815997.pdfIn PDF document text
    • https://tidaksusah.com/contents/files/80724965869.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/TxADE9PCSUw/uplcv?utm_term=good+riddance+meaningPDF 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_off0000d56d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD56D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED7F 18676 bytes
SHA-256: 5de602afe13b91795e3e8924af050a171c7cfe41f56ee7879e2d3ee480d2639e
font_02_sfnt_off00011df5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DF5 10440 bytes
SHA-256: 35225419896ec6ea53bc6e888cff1da39d4f2c968c2e2c4642acbd7b3c061523