Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4fd4ec1ab93d67b…

MALICIOUS

PDF

86.7 KB Created: 2021-07-15 20:42:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: bc7acd43bd9f8924466cfc3849a17f11 SHA-1: ea1ca438e526cd2f9259039f51de6a82f884c58b SHA-256: c4fd4ec1ab93d67b8f7591897a3769b9c133bc283c61742735e95f180c030646
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm pointing to multiple compromised WordPress upload directories, suggesting an attempt to host or distribute malicious content. While no scripts were explicitly extracted, the PDF structure and link farm indicate a phishing or malware distribution vector, likely delivered via spearphishing attachment.

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 https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/13ddf32edb34e24bac7bb8f533c809ee/piruzoziviwenew.pdf In PDF document text
    • https://maychieuvinh.vn/upload/files/38209902600.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e4e984739f---49616216231.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d52f408166---pozisuxezelexanopope.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4b9cd7b8bf---51772623232.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/5cc0f2ba0b088aa2ba05f2eb737e0080/89903001984.pdfIn PDF document text
    • http://yalciniskele.com/imgup/file/domijanefudujixujatesu.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/sqbi3pkkeoa3qcju347a9r85cs/44703113356.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/339df7fb1aef36ed92e442a1df89046a/87433267270.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/mawux.pdfIn PDF document text
    • https://udruga-invalida.hr/files/59364566681.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/034c556374112cff78d5ff079be6bbcf/50061646160.pdfIn PDF document text
    • http://xn--12cmi2byac9cdhd0hra6d7bxkwbgj1gch.com/user_img/files/jegakagisexuji.pdfIn PDF document text
    • http://kvbm.org/pds/userfiles/files/zunomesedekukisi.pdfIn PDF document text
    • http://seabeachthailand.com/UserFiles/file/69890646809.pdfIn PDF document text
    • http://tdbakademi.org/userfiles/files/9146438235.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/sn9avbhgd3080vfa459sou72l3/54535676780.pdfIn PDF document text
    • http://ownlines.com/upfiles/file/bumosoxujaretujepe.pdfIn PDF document text
    • http://houstontca.org/Content/uploads/files/jedaru.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608315edc26e4---38674987890.pdfIn PDF document text
    • https://stop-remont.ru/ckfinder/userfiles/files/81760406926.pdfIn PDF document text
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/9cf23e551c81e7bd337b78e138c4891a/20441162648.pdfIn PDF document text
    • http://nuestratierrapremios.com/campannas/file/topagapozutujagezut.pdfIn PDF document text
    • http://qianxish.com/ckfind_image/files/62906831624.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/160965de835e36---nitivutolumapumaxex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=nitrogen+cycle+and+carbon+cyclePDF 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_off0000f253.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF253 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A65 16560 bytes
SHA-256: 9d1928cece80d96a95f607db03469a13feb313f4b115e6d76292a13a180cb33b
font_02_sfnt_off0001354c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1354C 10608 bytes
SHA-256: 4d2e593246a29a5d65050174317a96e9c499f2525a5c19b39131ded6552ea3f4