Malicious PDF — malware analysis report

Static analysis result for SHA-256 950e3cae2571948c…

MALICIOUS

PDF

81.2 KB Created: 2021-09-18 01:46:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 39bc7ec0e921c2ea775ecbba8eea7c65 SHA-1: 973821c8c74e08ffa8a57a668248eff3f72a180e SHA-256: 950e3cae2571948c47189e3e8bc3fa39c184169f0f755b509f4512fa42509db3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file contains numerous links, many pointing to compromised WordPress uploads, suggesting it functions as a link farm to distribute malicious content or phish users. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/54bb5b7639c6a9bceb48b79a9eb2e95a/22180983810.pdf
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/217976d3c28417699228aa0623a3aa8e/wubomevazubixeb.pdf
    • https://divinenine.net/userfiles/file/wozevoninewa.pdf
    • http://vinhthuanvietnam.com/upload/files/93702389292.pdf
    • http://rm-centr.ru/uploads/file/63900706668.pdf
    • http://aeon-dev.com/uploads/files/202109010915092183.pdf
    • http://www.parkwaytransplant.com/media_upload/upload/files/vugopenusubowofukir.pdf
    • http://jnmindia.com/outscapes/admin/ckeditor/uploads/ck/files/rimifikekagefu.pdf
    • https://fundreamz.com/ckfinder/userfiles/files/xikojetemefomaneped.pdf
    • https://soudurelauziere.ca/upload/editor/file/fomixikuvelepuge.pdf
    • http://herium.net/FileData/ckfinder/files/20210904_C3ADC7B58202BF2D.pdf
    • https://marsanz.pl/uploads/fck/file/88250525171.pdf
    • http://hanhthien.net/uploads/file/65401973031.pdf
    • https://markaoyun.com/calisma2/files/uploads/satikefezizuzomuvasu.pdf
    • http://domplus.su/userfiles/files/78025671363.pdf
    • https://intrigantka.ru/images/userfiles/file/80108340288.pdf
    • https://okud-istra.hr/userfiles/file/lerinojol.pdf
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/dovaxexukoki.pdf
    • http://iktoktatas.hu/files/file/55358967819.pdf
    • http://classicalgardenfountains.com/uplds/file/37254846775.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/b6c6bc962d5dce16f461d53093fcfb9a/64634167890.pdf
    • http://posicert.com/upload_fck/file/2021-9-6/20210906220857696253.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=pocket+build+download
    • 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_off0000da8c.bin
92374779fa0eb71d39e587ce79f2a0445d0bb6572cccd55d845366b5f75c8a05
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA8C 10516 bytes
font_01_sfnt_off0000f2ac.bin
f6a847e83a82ada97d9fb19145a463d236bb543394e34c88bfc2a849a8896aea
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2AC 17084 bytes
font_02_sfnt_off00011f19.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F19 16792 bytes