Malicious PDF — malware analysis report

Static analysis result for SHA-256 e52646f102ba07d4…

MALICIOUS

PDF

74.3 KB Created: 2021-09-23 12:58:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e0513a1b33006ed087bfc7d83deb0ae0 SHA-1: 93c361d04f3b30a0a945acba45bfc998a9367207 SHA-256: e52646f102ba07d4468a524c497f517b0f45d95caac20894735eb7896e8a03a0
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but likely serving as a container for the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://nomylo.ru/uplcv?utm_term=medal+of+honor+airborne+android PDF link annotation
    • http://gkz-crimea.ru/userfiles/file/4389885908.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/l236muqcphjoicca459st1ual6/duxonova.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/guxalupanurekonani.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/6439386019.pdfIn PDF document text
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/60870746018.pdfIn PDF document text
    • https://propage.q-cloud.net/upload/ckeditor/pages/files/10101122.pdfIn PDF document text
    • http://aotwresort.net/ckfinder/userfiles/files/73555436879.pdfIn PDF document text
    • http://agroanaliz.by/upload/editor/files/pijurid.pdfIn PDF document text
    • https://teamcode.net/upload/files/90335502237.pdfIn PDF document text
    • http://nfrostov.ru/upload/files/wopadurorudeviwagig.pdfIn PDF document text
    • http://ecovn.vn/uploads/news_file/71552695187.pdfIn PDF document text
    • https://krantiservice.com/ckfinder/userfiles/files/sewidevukutotamu.pdfIn PDF document text
    • http://uptownfallschurch.com/uploads/files/94943891623.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eedf0f4124---38524504573.pdfIn PDF document text
    • http://xdata.pl/app/webroot/img/ckf/files/69128455193.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161381cc20f7e2---60451911948.pdfIn PDF document text
    • http://urbancollab.com/userfiles/Proj_Name/files/depusigobudobotokewukudo.pdfIn PDF document text
    • https://ikomsolutions.com/admin/userfiles/file/pojofevisexolosixigedezu.pdfIn PDF document text
    • http://way-of-spirit.ru/upload/file/verelewawejuf.pdfIn PDF document text
    • http://hanifeugur.com/image/files/mosoligejekagupobor.pdfIn PDF document text
    • http://cortocircuito.trialpanel.com/images/Upload/files/32909236032.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f19e65db6b---zifaxukumagunadopasovox.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_off0000be56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE56 18020 bytes
SHA-256: 94f8d2a2632045eca0331e1ab4945d64e51a4c2bc274775f1b08b482fec59aee
font_01_sfnt_off0000ecd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104F0 10320 bytes
SHA-256: e6b3f8bd61a2634490d74bdd05c7b60935ade3e9206ac3f5c145ce2ed27d9eec