Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c6a5a98722cb034…

MALICIOUS

PDF

72.8 KB Created: 2021-09-27 06:06:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 015d34d3025bd7e9282670f14eeb03fb SHA-1: 9d32d9efec0dfaeaad4b0f3e66d0581d6de7ef72 SHA-256: 4c6a5a98722cb0340e88dd23cde5c9bd34ad2ecc9cb3d263bf007c9ef71c1fa6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a large number of embedded URLs, many pointing to compromised websites or domains designed for SEO manipulation. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the heuristic findings clearly point to a link farm used for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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=sword+art+online+season+1+episode+24+english+dub PDF link annotation
    • http://delfosventures.net/userfiles/files/86794702805.pdfIn PDF document text
    • http://clubsahdianagalati.ro/upload/editor/file/53608017710.pdfIn PDF document text
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f342a443c7---tubiwetovitev.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/8b5946111b6ae4ac7bc8e453aa9362a4/95535214787.pdfIn PDF document text
    • http://restravel.ru/ckfinder/userfiles/files/wovazekafoxosukame.pdfIn PDF document text
    • http://movesearchesuk.com/userfiles/file/78635218538.pdfIn PDF document text
    • http://toyotarent.hk/FileData/ckfinder/files/20210919_F9ED0B3A0341DF43.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/142331d8e2b8e340155215959b840d9f/86796936591.pdfIn PDF document text
    • http://foodzipo.com/uploads/userfiles/files/kopuzisuwozemaxodadagoji.pdfIn PDF document text
    • https://abss.pt/userfiles/file/22305029470.pdfIn PDF document text
    • http://giprozdraw.ru/ckfinder/userfiles/files/juzumidujagefegorenunaj.pdfIn PDF document text
    • http://djapm.com/userfiles/file/liberigitujes.pdfIn PDF document text
    • http://www.darvidproperty.com/news/file/243999817.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/8718ff7c1a3c3e34d2ce670f009fd5d4/nijezafo.pdfIn PDF document text
    • http://craj-ops.craj.cz/soubory/33644252366.pdfIn PDF document text
    • http://lepetitjaunais.com/userfiles/file/kigedif.pdfIn PDF document text
    • http://maturitni-ples.eu/UserFiles/File/4281132683.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/72414283878.pdfIn PDF document text
    • http://jatechkj.pl/upload/fck/file/25226325668.pdfIn PDF document text
    • https://tresonance.org/uploadfiles/39252742806.pdfIn PDF document text
    • http://vendsol.com/userfiles/file/58529733525.pdfIn PDF document text
    • https://designclarf.it/file/kizibeton.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/rijukit.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_off0000b3e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3E6 11324 bytes
SHA-256: 50f29b91f4e1ced8559eae32fb9144260011607f679c8031e0ab245075eef801
font_01_sfnt_off0000ce2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE2B 17824 bytes
SHA-256: b74062a982863a269749426bbe042064945b595040b6dac8f388ed24159a23f0
font_02_sfnt_off0000fb8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1