Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e3cb03d42d11777…

MALICIOUS

PDF

71.1 KB Created: 2021-09-30 18:26:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4e69819edf1dee27f6aa8cedc33581d7 SHA-1: 1f7be17bb61835c812a392108c0db78d6e25d927 SHA-256: 8e3cb03d42d11777f8470ed5519c2cc11fd8f4d38c4ea1b0ae2e0ce1b5ba9f94
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, flagging it as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to potentially compromised websites and disposable hosting, likely to distribute malware or conduct phishing. The presence of SEO-related terms in URLs suggests an attempt to manipulate search results for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://irlanc.ru/uplcv?utm_term=score+hero+hack+mod+apk+download PDF link annotation
    • http://kibbkw.com/uploads/files/77023288193.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/75515910155.pdfIn PDF document text
    • http://heldermusic.nl/ckfinder/userfiles/files/53278145277.pdfIn PDF document text
    • http://malir-naterac.info/UserFiles/File/3852386141.pdfIn PDF document text
    • http://joyear.com/ckfinder/userfiles/files/69031259806.pdfIn PDF document text
    • https://mountainbrookbuilders.com/home/mountain/public_html/ckfinder/userfiles/files/jugotub.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614530c1de829---79821125671.pdfIn PDF document text
    • http://beganijewellers.com/ckeditor/ckfinder/userfiles/files/84264831484.pdfIn PDF document text
    • http://cbstav.cz/file/91650744727.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1614357fb8045b---67596589988.pdfIn PDF document text
    • http://tvkinter.com/file_media/file_image/file/74079944622.pdfIn PDF document text
    • http://hoachathoanggia.com/userfiles/file/sutodaperunikexu.pdfIn PDF document text
    • http://bienbao.org/uploads/files/papafulif.pdfIn PDF document text
    • http://anton-joyeros.shopcloud.es/ckfinder/userfiles/files/77252725531.pdfIn PDF document text
    • http://softwaretesting.kr/club/data/userfiles/file/20210915225755.pdfIn PDF document text
    • http://suchanekstomatolog.pl/files/file/91600516970.pdfIn PDF document text
    • http://kazuma.ru/ckfinder/userfiles/files/xatosasoba.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/3f11111d79322eb53985a0088e0df090/rawobowimivaz.pdfIn PDF document text
    • http://globalfeedindustry.com/upload/files/xikam.pdfIn PDF document text
    • http://consade.com/userfiles/file/nidanugoruwesipumofeno.pdfIn PDF document text
    • http://dryoucosmeceutical.com/userfiles/files/38685571713.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_off0000b10f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB10F 17736 bytes
SHA-256: fa4f5eeb4664aa8660f39fb316bc060e5d1f6bbeb7ed46557d3ad741d5f5c1de
font_01_sfnt_off0000de4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE4C 10676 bytes
SHA-256: 1366062224eaa4b9a0df84801091c84277287a52defff740274ffd3e0ce25b49
font_02_sfnt_off0000f6a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1