Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae11675351e652f6…

MALICIOUS

PDF

86.5 KB Created: 2021-07-02 17:04:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a52bdf19749182a20462f5211aa28ad1 SHA-1: 1cd8d8d362f7b133ac72f83d02fa9c903f546b2a SHA-256: ae11675351e652f62e3e5436e15b789226edbd3ba120b67c9b08658110febdae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to external sites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://inwebjor.ru/uplcv?utm_term=wall+painting+spiderman
    • https://recapress.com/ckfinder/userfiles/files/39780251609.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608f02fe9058d---43343399959.pdf
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5e2bdc911---zupuwi.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/1dbfb1a5af76dab8314292a066ccb730/veweniwikurijolevexo.pdf
    • http://to-tuong.com/media/ckfinder/files/fanixozubuk.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607409a9a2b93---wuvejevibuzas.pdf
    • https://ocw.tw/uploads/files/furixerugufelaniginiloruv.pdf
    • https://coevent.ru/upload/files/zenilagivo.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608252b5dd9ef---gavusap.pdf
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/64d7c799b3cf3477f690a532ded7978b/28885739139.pdf
    • https://rubyyadav.com/nbloom/fckuploads/file/89886555452.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/75013253c6cabd58a8576d1f0694b2b8/femexoxumorenonekej.pdf
    • https://washlounge.in/ckfinder/userfiles/files/5812896748.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086e27a951e1---8263436708.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089e52a547dc---86315427062.pdf
    • http://akgikorea.com/file_upload/fck_upfile/file/1698007135.pdf
    • http://azbuka-d.ru/ckfinder/userfiles/files/bematafabelofa.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/pq41694jblid4rbgfkcdbao186/nidaxon.pdf
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/c93e1bdb1ded89c08821b020ba594e28/fizobugagukizuw.pdf
    • https://nibrasimansch.com/userfiles/files/sijexerilazu.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099d3ac1d4dc---82447217032.pdf
    • http://berallebags.com/UploadFiles/FCKeditor/20210517033837.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_off0000f05b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF05B 16792 bytes
font_01_sfnt_off00010872.bin
4e27d2ec602168cc70ff4333b91d6841607d8beb9ebcf33069c22afe3b46985e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10872 10608 bytes
font_02_sfnt_off00012078.bin
32280b9e4f092702ee6106c5a6192941e9a367c12798ccf9b6416b9400c8529f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12078 17196 bytes