Malicious PDF — malware analysis report

Static analysis result for SHA-256 353468161264dce1…

MALICIOUS

PDF

89.8 KB Created: 2021-07-09 12:56:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 24ea2e4653d43027dd8d63eec0787e19 SHA-1: 3ea6815ad285164aebae7832c73c19ba6af6ff37 SHA-256: 353468161264dce18713a3402de7cb6dd4332f7847b7bd5d212a52950bb06624
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with heuristics indicating it functions as a link farm on compromised CMS uploads. The embedded URLs point to various websites, many of which appear to be compromised WordPress installations, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the PDF structure and URL patterns are consistent with attempts to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://altinellerinsaat.net/UserFiles/file/23628153375.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160702c9e902c3---nimitu.pdf
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160964123b23cf---sodelokez.pdf
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/520d7b4832f330b4196b3ff76707f08c/sezorufil.pdf
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160d367cf9a9ac---vutudujakezabuzoxurid.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/303aoeupccc13jbjlledgpb326/23624480215.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e8ba25a68---ropamowiwu.pdf
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160816c5a7286d---guzinogovakobezesufadumeb.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608b416552a5d---71717474368.pdf
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/83a614adbb9d6fe4b64859785a73f75f/semale.pdf
    • https://tenfci.org/userfiles/file/zajalajanak.pdf
    • https://x-software.cz/data/file/26900681421.pdf
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/03353400425c701020ba8b8387550666/74972749071.pdf
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/jezuzegafiduzazek.pdf
    • http://nguyenquangcomputer.com/upload/ck/files/mudigafexiginedajanox.pdf
    • http://coyada.com/up_images/up_images/32064073166.pdf
    • https://davebakeragency.com/wp-content/plugins/super-forms/uploads/php/files/7e8f267a592ff2bde2108c5c1336f06b/4129387951.pdf
    • http://spoanalyze.com/wp-content/plugins/super-forms/uploads/php/files/32a01650fda6a6d36d472c8e4e805b95/46778153264.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071435ea013d---82021357781.pdf
    • https://cristalparkhotel.com/ckfinder/userfiles/files/dalunuvuvuli.pdf
    • https://camping-du-lac-dijon.com/fichiers/54670340998.pdf
    • http://handbook.hu/upload/page/file/91507153991.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=t+value+excel
    • 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_off0000ff5f.bin
a5c139b9a6b43d1678b2e9a2b84bbcaa4497e861bbebf6424546ecf991833618
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF5F 17352 bytes
font_01_sfnt_off00012d12.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D12 16792 bytes
font_02_sfnt_off00014528.bin
d7d3bca6b9302cd207a17d215965cbd057d22aee3f13ffdf46cde8423f1d9dfd
pdf-font-stream PDF embedded font (sfnt) at offset 0x14528 9772 bytes