Malicious PDF — malware analysis report

Static analysis result for SHA-256 503d939e69aa9be0…

MALICIOUS

PDF

78.8 KB Created: 2021-06-21 00:12:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: aa88793c4ab6a81b4aa2a88dfddd6334 SHA-1: 537c2c7c0d6630775794eab5523a671b5eedc85e SHA-256: 503d939e69aa9be0a102b20d724655aa2dc4530e9249fdcd1a5df0e7c600bd52
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085caa715454---videjaritonuwosojizonixo.pdf In PDF document text
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/vuvelikopekamajaju.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/affcc1325afc077416aaea4e02f46155/kagabolozigazikodaju.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/23582523096.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086be117cfc4---22377879470.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098463852a7a---87416765820.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/748c791d8f6eb986819b07a9ab3a9d77/tajonipisomosija.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/bkc01820hiid3vr55kejk8n353/88679042821.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b28f1931819---zapolavuzazudanoxetukavef.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/4a04a0110187fd4ecc4ce5db3a028365/telebar.pdfIn PDF document text
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/48rava27cjom8uccfm60a1pmrk/18336313326.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/72790d241cdcc10964b690939726a383/bejigixepojuxelugukelaro.pdfIn PDF document text
    • http://aaykpn.com/uploads/editor/files/domexubom.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b845ce3f49c---fobowejaxuserapixiwur.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=shivaya+namaha+unnikrishnan+songPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d68f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD68F 5396 bytes
SHA-256: 3f66b1dd61805774778a17c0c47cb46392afa777fbd6d8dc94211f6bd879c76d
font_01_sfnt_off0000e8c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C6 3172 bytes
SHA-256: b95d051f80b4b8ef2cc03394d0d836c96e967ce611ee1338cf9ae8be74f8d885
font_02_sfnt_off0000f58c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF58C 12548 bytes
SHA-256: 4ed4d14cf5b8bcd4f39037f9e4a61a275b2781fb4112366bb882547840fe8da6
font_03_sfnt_off00011ea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EA5 3492 bytes
SHA-256: d92d7f41df2d27f9893b7e95333e2195705b76487f9272be291be935b826ab42