Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c7d2dd8f13ac2c9…

MALICIOUS

PDF

82.5 KB Created: 2021-09-03 23:37:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6099baef4530fac76debc79a6e2e0465 SHA-1: 424d707ee89f8faad83995a34c65367ce4875ca6 SHA-256: 3c7d2dd8f13ac2c94da622b3d4e8945055e3a683724b120136d9f669189fc90d
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of multiple links on potentially compromised or disposable hosting reinforces the nature of this document as a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/5ko1585t88cbo9blk8nl99vk6a/95264454045.pdf
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608631080273f---vajarifojokoxagokebevov.pdf
    • http://www.mostex.sk/files/articles/file/81592684513.pdf
    • https://oteaexpert.fr/cite_imgs/file/torujovukupaxedoje.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16124d7aa65288---90165486301.pdf
    • https://houstoncoinshow.org/FCKeditor/file/99406252694.pdf
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/acdbed4a11fd72d96eb35c156abe0fea/18033732386.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612bf59c07db0---74888710996.pdf
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160783ca743a89---97380275581.pdf
    • http://arci-mp.fr/admin/File/gonefunemonepadikewi.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ab94fcd9e15---53610041139.pdf
    • http://hsound.ro/images/custom/file/69761152252.pdf
    • http://mrukseo.pl/userfiles/file/zexemoxamizegemugit.pdf
    • http://irk-yoga.ru/upload/files/dexopofokafol.pdf
    • https://nevisnews.com/userfiles/duwaf.pdf
    • https://belhasasecurity.com/userfiles/file/xonawofoxi.pdf
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/b7510034a2e386f9a32d9c14ccbd0fa9/xesadidivobilozone.pdf
    • http://saltokisport.com/uploads/files/nojipinemavefexu.pdf
    • http://okzawidow.pl/img/upload/files/25967936197.pdf
    • https://ags-car.com/upload/files/9195595087.pdf
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a38c2c093c9---16927636354.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=cvc+words+activities+for+kindergarten+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dba7.bin
b5ab7dd1b2d89956552ac633eefe6312147ba8d402e833af7a4230e4cb8aef3c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA7 11024 bytes
font_01_sfnt_off0000f54d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF54D 16792 bytes
font_02_sfnt_off00010d5f.bin
8c906bff389fe86b890a340cb8d6308b82559f4043ca0ea841d6f3f4f8693e43
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D5F 18000 bytes