Malicious PDF — malware analysis report

Static analysis result for SHA-256 19a190aa05cb36c7…

MALICIOUS

PDF

71.6 KB Created: 2021-06-21 08:10:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: f6c43f8ddf335f1c67164b37c8417c1f SHA-1: 363ea336dd3be126e0db69b2bf736e6ec022742c SHA-256: 19a190aa05cb36c7d7e3de4ab6f633998ba75e67f266c54a49032417b0aac294
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://stardentalcare.org/userfiles/file/jipakewemobiwefevizebogib.pdf In PDF document text
    • http://coffee33.ru/archive/file/rupixo.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/de35i4ahoknt84c8r71j38tj4v/40941577778.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/33h3vc0prun7gbgd1t2sdoupmi/7335524039.pdfIn PDF document text
    • https://alyosserspneed.com/userfiles/files/37438126168.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/lnecop3plcfmu1ovbp3il5i2dr/64031089467.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/nugagubofika.pdfIn PDF document text
    • http://vietxetai.com/wp-content/plugins/super-forms/uploads/php/files/bqs4pegaj85ubh576p17v8j0kd/68135845800.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/594825bd622095e25c686dd1cd5f1893/piladu.pdfIn PDF document text
    • http://bagumul.com/file_upload/spaw_upload/file/20210621103058.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160abadbc07ddf---bupuboruligezipofedi.pdfIn PDF document text
    • http://sixtyguildersresearch.com/admin/photos/file/bidekufisijumirifigisabit.pdfIn PDF document text
    • http://interel-rus.ru/test/sites/default/files/file/xotixive.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/e89e2fa0b2c99cf3a13e260492740ac4/6770753423.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/65983536412.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=outlook+mail+free+download+for+windows+10PDF link annotation
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dad9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAD9 5428 bytes
SHA-256: a82dbf10e51f1bf70ebe108812e5ab9eca8fd133d71df9982cb41831d183bab9
font_01_sfnt_off0000ed53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED53 10636 bytes
SHA-256: 4a8ccd432a2acba497fa084acf206e789d4c900cb7a99c69af5380fc97c6d66b