Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cf3762fa0dfb1a8…

MALICIOUS

PDF

93.0 KB Created: 2021-09-08 22:11:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 23740b80984d6b0ed9bf366242c136ef SHA-1: fd791173eea02c473ae17aab04ec5f19e7f1b526 SHA-256: 4cf3762fa0dfb1a865dc232aacc8810fc94f7c9dd0b13fa070bc361ecd71ee42
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to potentially compromised or disposable hosting. The embedded URLs suggest an attempt to direct users to external, untrusted resources, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://geyikkimya.com/userfiles/upload/file/19491786734.pdf In PDF document text
    • http://ets-sptk.ru/pic/file/ridupugudonavi.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/21705258349.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/boseloli.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16132ffe36235d---70191340482.pdfIn PDF document text
    • http://datacomsystems.cz/userfiles/file/zigamiked.pdfIn PDF document text
    • http://kssi.ir/public/userfiles/file/nesizojibelaxugagisegu.pdfIn PDF document text
    • http://greenmodels.ru/uploads/files/sutibog.pdfIn PDF document text
    • http://ecovn.vn/uploads/news_file/99666066975.pdfIn PDF document text
    • https://aokman-drive.com/d/files/6923020287.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/29932774988.pdfIn PDF document text
    • http://skoleniridicubrno.cz/ckfinder/userfiles/files/voxitavuwalekoxipod.pdfIn PDF document text
    • http://buyyoutubecomments.com/ci/userfiles/files/86958397980.pdfIn PDF document text
    • http://www.tramag.pl/upload/file/sorilunelajudodeze.pdfIn PDF document text
    • http://staresecurity.com/userfiles/file/83429203174.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161326d0fb6876---zeluvubosiduko.pdfIn PDF document text
    • http://rubivina.com/Images_upload/files/dalapaduvilosobaviwa.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131543b476f9---89252474318.pdfIn PDF document text
    • http://canavesiobruno-architetti.it/userfiles/files/bojoguxaxufu.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/670283c809bb6e4d893c835eb0cda035/megajamur.pdfIn PDF document text
    • http://abwlanham.com/uploads/files/27421953306.pdfIn PDF document text
    • http://erbamedica.org/userfiles/files/rokaw.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/sanudaxixovaxegu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+get+free+14+day+ps+plusPDF 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_off00010767.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10767 17884 bytes
SHA-256: a8a47c8186d2de7bad780648a4995577366f78020d9a389d6f58cf363ec73780
font_01_sfnt_off00013563.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13563 10896 bytes
SHA-256: 1cc96712c5acbcd625fbfc58ed39ab9572b567179e9f2a4a0d33bf0d15863862
font_02_sfnt_off00014eba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EBA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1