Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b69ccdc30017508…

MALICIOUS

PDF

73.4 KB Created: 2021-09-18 08:04:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 971d0d8abe4566e2e6b0339d91fce7bb SHA-1: 489887072afaff58f10f542663249abe2b203e21 SHA-256: 4b69ccdc3001750892f0b183a13acc6824740f5d55ac5d3f527d897c3e2d949b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which are flagged as link farms or hosted on compromised CMS uploads. 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 are sufficient to infer a malicious link-farming attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://jnmindia.com/outscapes/admin/ckeditor/uploads/ck/files/mozebimopumudusoz.pdf
    • http://ahjygjg.com/upload_fck/file/2021-9-1/20210901073443489631.pdf
    • https://ermolino.mebel18.com/uploads/files/26502746136.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/16131260ac901d---boxuxumanipe.pdf
    • http://olympicburger1988.com/uploads/files/zinasutewiwurib.pdf
    • http://tivatijapan.com/uploads/userfiles/file/pozud.pdf
    • http://www.insight-assessment.com/ckfinder/userfiles/files/zanexapevitox.pdf
    • http://gayaarchi.com/userfiles/file/20210913075321.pdf
    • http://www.libroparlatolions.it/backoffice/ckfinder/userfiles/files/bonipiforifibux.pdf
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/dd4c18e04bc9cdf4d5cf55f1b097eed0/70423286765.pdf
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/161451e2a530ef---xagixedijesinijumije.pdf
    • http://bularz-auto.pl/images/userfiles/file/16831077475.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613d11164e67c---13516957984.pdf
    • http://elpijisystem.com/file/wijetizepokesefud.pdf
    • http://www.musicboxpiano.com/contentfiles/32981766572.pdf
    • http://wawabed.pl/uploads/userfiles/file/mosabegefolet.pdf
    • https://iieng.org/editor/ckfinder/userfiles/files/3919256471.pdf
    • https://quizai.com/uploads/files/zalidimimegif.pdf
    • http://pileki.com/imgup/file/fijizokus.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/161439eadba70f---rawizi.pdf
    • https://www.funes.gob.ar/ckfinder/userfiles/files/jowomulegologugobina.pdf
    • https://rwd1.thadv.com/upload/files/89822780744.pdf
    • http://alpinedelhi.com/userfiles/files/fagugawujid.pdf
    • https://basealimentare.it/webroot/files/fck_uploads/File/51084505835.pdf
    • http://lindendirect.com/ckfinder/userfiles/files/83644544025.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=paul+simon+still+crazy+chords
    • 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_off0000b8e7.bin
72d1ac6962b0153b498572d6c75e035004478cbbe0c474c8508c2a5a6de8fb9e
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8E7 10780 bytes
font_01_sfnt_off0000d198.bin
d21f8cb31b56b78e5f920f88950474c78b7fd007daa768326800e15e307083a7
pdf-font-stream PDF embedded font (sfnt) at offset 0xD198 17924 bytes
font_02_sfnt_off00010078.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10078 16792 bytes