Malicious PDF — malware analysis report

Static analysis result for SHA-256 527c4ae8c61afe42…

MALICIOUS

PDF

87.5 KB Created: 2021-07-28 00:46:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9034b463e1ceb33ff676f54a3383c2f7 SHA-1: fd6fee3a9ac68c3b929ed38e1a4686a18a8b7acc SHA-256: 527c4ae8c61afe420ec8f7852489c834178e3bb4a3a4f57f4b65d368a6265640
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as containing a link farm and pointing to compromised CMS uploads. The ML classifier and ClamAV also identified it as malicious. The presence of numerous URLs, many hosted on potentially disposable domains or compromised sites, strongly suggests a phishing or malicious redirection attempt. No scripts were extracted, but the document's structure and URL patterns indicate a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://tribo.kz/userfiles/File/80454554895.pdf In PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/jk42qhhn1a423he7tqib64e6l0/kuvifigideseminim.pdfIn PDF document text
    • http://qa-whg.net/upload/files/figaveduxur.pdfIn PDF document text
    • https://fceresources.com/ckfinder/userfiles/files/22014536082.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/85505641934.pdfIn PDF document text
    • http://sfera-vlad.ru/img/file/nidesidafusilowek.pdfIn PDF document text
    • http://gatewayhotelbangkok.com/upfile_hotel/files/44744125101.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3aa50d3da2---fexoxibunapodexogo.pdfIn PDF document text
    • http://wolfroccatiassociati.it/userfiles/files/mumipemofufodononixonufag.pdfIn PDF document text
    • https://bibliothequeanglaise.org/upload/files/56536360037.pdfIn PDF document text
    • http://livestocktool.com/d/files/86520624861.pdfIn PDF document text
    • http://insfilings.com/skyzone_classic/upload/files/zozajefidosefofi.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/25769277628.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160849b4712b9f---diviworuxituzi.pdfIn PDF document text
    • http://greaterdeliveranceministries1.com/clients/61527/File/28239164795.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/begowoweko.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607231267c8f8---febupagubuvugusab.pdfIn PDF document text
    • http://sola-brothers.com/userfiles/file/gugaparevekid.pdfIn PDF document text
    • http://korvet-sp.ru/userfiles/file/pigedofukojodemubu.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e63637ab61d---30309531504.pdfIn PDF document text
    • http://eprdel.cz/userfiles/file/22117430414.pdfIn PDF document text
    • http://championshipsportsrings.com/clients/23492/File/29564616813.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/c98307c2bd2017b8efac90b6927790a0/zanamejepuzizosu.pdfIn PDF document text
    • https://vinaconexmec.vn/uploads/news_file/8142182558.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=finding+missing+angles+in+quadrilaterals+worksheet+ks2PDF 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://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_off0000f0f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F6 17016 bytes
SHA-256: b545d9f7cfd1618afeecf67c39ab830cc0cbf13bfddfff1462a738e9a1c7f03f
font_01_sfnt_off00011d70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D70 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013587.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13587 11216 bytes
SHA-256: 0cef65f0bbd36ca871fc5668020ad1516bcbbd12026d481b94c98921cda0026b