Malicious PDF — malware analysis report

Static analysis result for SHA-256 670de21b19ca7477…

MALICIOUS

PDF

76.5 KB Created: 2021-09-06 05:34:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 56f2649a1ab6c9dbeda52cad7ef99cc5 SHA-1: bb87c008945a95834f1b3710899d047d0e4717f8 SHA-256: 670de21b19ca7477220b7d36edaf581455ea13c6f3a3f46c60c4516c03059eb2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://oniceh.ru/uplcv?utm_term=imperative+exercises+elementary+pdf PDF link annotation
    • http://phoiinnhiet.com/images/uploads/files/24214209526.pdfIn PDF document text
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/gorupobalejolodilepe.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fb97f3aa0c7---nomubexat.pdfIn PDF document text
    • http://www.farmaciabergua.com/userfiles/files/visibebire.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/c2d594aef8ff4459105ba0601557829c/46630965933.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/3d8845d6f6ec3dd99fb7bf71dc2619cd/wejuvedudu.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/36324333955.pdfIn PDF document text
    • http://epmachine.ru/d/files/zofegemixo.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/ag8m1r163o6alql07u89d4r960/67169526527.pdfIn PDF document text
    • http://cuoredicane.it/userfiles/files/jugulevunejamowas.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/vsssesdm08esn0f8m17vsrgt8l/8652257659.pdfIn PDF document text
    • https://hippodrome-compiegne.fr/www/uploads/file/6938938774.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/15695522892.pdfIn PDF document text
    • https://larrialdiak.es/files/galeria/files/sepawekodonixavogerupivol.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-6-29/20210629031129168997.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/098d4128a368da6262dc3de921cafe31/1761298840.pdfIn PDF document text
    • http://sonnenheizung.ch/fckeditor/editor/images/file/41400975941.pdfIn PDF document text
    • https://karpzbeldowa.pl/uploads/userfiles/files/14966038946.pdfIn PDF document text
    • http://biafrapol.pl/pliki/file/dodedofawozev.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/1e9c848f27e611098a7d1e1a0547dd5a/fugevimuvedunigob.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/968773d28ae4ed7ab74523400c934fa0/75476431239.pdfIn PDF document text
    • https://magatek.com/documents/file/50309730008.pdfIn PDF document text
    • https://grupo.iberia.es/js/ckfinder/userfiles/files/nizejutoxoj.pdfIn PDF document text
    • http://philboyd.com/zadoduzijoniwulesiban.pdfIn PDF document text
    • https://austdoorcaocap.com/upload/files/22526238036.pdfIn PDF document text
    • http://coinproject.com/userfiles/image/file/88048357006.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_off0000c790.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC790 16684 bytes
SHA-256: 9b4d11d640d7f2f93f7c51b77108fc4e9abee0db4137fff68a294dd9f779f4d0
font_01_sfnt_off0000f26e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF26E 10892 bytes
SHA-256: 22baa48609ac3a863c1f5a79ce0f927ff4f7d339c956b47d91a5ae7f17b1f82e
font_02_sfnt_off00010ba1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1