Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5525636405a0cfa…

MALICIOUS

PDF

80.4 KB Created: 2021-09-17 06:47:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 86f938e3d7c87634bbcf433d41466916 SHA-1: 3c0672978ee2a48762634aea4ef55b438415d394 SHA-256: f5525636405a0cfa8a8a4d869cd48c4a06ec639fbe67b710bbd29533ea2086a5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and link farm heuristics, indicating an attempt to redirect users to compromised websites. The presence of embedded URLs and the nature of the heuristics suggest the document's primary purpose is to facilitate malicious redirection, likely for phishing or malware distribution.

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://krisoc.ru/uplcv?utm_term=marvel+vs+capcom+para+android+download PDF link annotation
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/1ea543cbac25570d2b6fce0756e1d642/garirewiwu.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613f7809f3236---78605208290.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/kejejaxak.pdfIn PDF document text
    • https://machnik.net/ckfinder/userfiles/files/kosedexaz.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/befapa.pdfIn PDF document text
    • http://schokofontaenen.de/idata/45731379952.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/mojoguju.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/dirasatim.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/gagofetuwawapotuzirekibo.pdfIn PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/25281271828.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137858845b51---4461542874.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/61650546953.pdfIn PDF document text
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/35334723902.pdfIn PDF document text
    • http://xpeedon.net/userfiles/file/20210906135450.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/rumaweboxakadojazifimoro.pdfIn PDF document text
    • http://pevak.info/UserFiles/File/doninofofesaxevefisax.pdfIn PDF document text
    • http://naturalmis.com/userfiles/file/terofujunigoxivagiza.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/munepibelobuxa.pdfIn PDF document text
    • http://kanchanaspa.com/ckfinder/userfiles/files/vababasozujagibekovomoge.pdfIn PDF document text
    • http://asfalon.com/__files/file/80897104587.pdfIn PDF document text
    • http://mashhadgardi724.ir/basefile/mashhadgardi724/files/woxanatuwirapos.pdfIn PDF document text
    • http://royalwedding.jp/images/blog/file/xedovesufuxuvifepesowaji.pdfIn PDF document text
    • https://peusch.lu/userfiles/files/41185376901.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_off0000d522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD522 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED39 10720 bytes
SHA-256: 5380d3115727c2dc3ffe98aa38d33c658c746db0b555b40fc94d86e649c440c2
font_02_sfnt_off000105d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D3 17656 bytes
SHA-256: 3bfb45316552182d4dd8e45558803fa0a4647c92972d81cc63f9be66a27efa10