Malicious PDF — malware analysis report

Static analysis result for SHA-256 49a17ae9c1408683…

MALICIOUS

PDF

87.5 KB Created: 2021-07-19 00:41:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 00303c103b8769363c222fdf9cdf68fd SHA-1: 3b14c9fb02cfb82945d5cced12269483e2d016ab SHA-256: 49a17ae9c14086839cf556b3971d3e2d14950b3795d24d9579d508040824e1b1
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, with high-confidence heuristics indicating it's a link farm pointing to compromised WordPress upload storage. The PDF contains numerous URLs, many of which are hosted on potentially compromised sites, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the PDF structure and URL patterns are indicative of exploitation or redirection to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/597d00cd6e920f78aaa4c490541a6db0/34488791650.pdf In PDF document text
    • http://whs1979.net/clients/65916/File/31525674461.pdfIn PDF document text
    • https://airflow-skateboards.com/upload/file/97563357292.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c412efc9e22---mofupamuvujipomexudokup.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b464c7aabb---77697415344.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/70019384372.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160927955c3ae2---jimuwinerebomifafef.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/629e59fefda7f61c1652d86d3b07cc59/46818626069.pdfIn PDF document text
    • https://forthepeoplegov.com/userfiles/file/40497766260.pdfIn PDF document text
    • https://signika.pl/Upload/file/bafuxumujikidorujufe.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/3432ff0c44b93584caa3f00bd30a7b18/felukizofudimakuzunodetif.pdfIn PDF document text
    • http://eventologia.com/userfiles/files/xevavulugip.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/da855af40bc6eabf90c5c89c8b83fae1/18349545359.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfd7e2ecf7a---jiduv.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2d921050aa---20113534001.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/bff18ca2f58a47a261e573a46b48439f/25417724614.pdfIn PDF document text
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160afbac70b68d---tilof.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/87056718735.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/vemetezuk.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/fisogi.pdfIn PDF document text
    • https://meganimal.pt/site/upload/file/41039423928.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/tidisawomipomajurebuta.pdfIn PDF document text
    • http://emannsltd.com/userfiles/wetamov.pdfIn PDF document text
    • http://cymagun.com/userfiles/10019766027.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8c0112af12---fuxokibotube.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=tamil+birthday+wishes+for+brotherPDF 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_off0000efe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F6 18944 bytes
SHA-256: 89601c7feb1358d88fddcf8e16c52e9898cc4d3a0da31a1629bbbe9fb18bb1e1
font_02_sfnt_off000137cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137CB 10820 bytes
SHA-256: 198b340a063be2796afeb38964f53e56e48eea4f3f20ab9dbfc6d385c05fc1d6