Malicious PDF — malware analysis report

Static analysis result for SHA-256 81f2759fb4336153…

MALICIOUS

PDF

80.2 KB Created: 2021-04-30 21:38:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 1176f3df3df2c97f7bb8f9a46dc53461 SHA-1: 3ea754c9b02d1c4f37ac7d1467de05978007d685 SHA-256: 81f2759fb4336153f2035b5317987813f6ffa72d702a00737285e207d6797b87
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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nutricionintravenosa.com/wp-content/plugins/super-forms/uploads/php/files/4ba066617a497f09496bae0571a8df2a/45204655001.pdf In PDF document text
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/1785f37f3af1272db8ee556b7fa769d9/laxalofemeravevigoli.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160742704b7042---72915768042.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071aa2220a3c---vodifi.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160867eb2c81c7---zaxesupuxo.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606f29be0909c---21438114028.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/89bacff98c7746f1785172028dde0d3d/92476453504.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/048e5423ff0857d91544b6aca6853eb4/zawimuzetisaxalerebov.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/ef2b56f7aff4a63ef4bb8f977234795a/36591609491.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089bf67b4c82---gagim.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/16078e8ca26a42---kisarixewujoxile.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b8208a0625---tazonudafirixaxis.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/3fb98812ff9cb08306291560ffc09123/wajexiwadononut.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608273130d835---78914792451.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=cisco+ir800+datasheetPDF 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cffc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFFC 5200 bytes
SHA-256: 7b300b1bebb62087e16498911487c6c3fbc773194999be025dd5d0b2bafe3316
font_01_sfnt_off0000e226.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE226 5236 bytes
SHA-256: 86788c671c2c2456ff757cf64b6d236983c23ee4128643027dd96ef017754577
font_02_sfnt_off0000f3eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EB 11480 bytes
SHA-256: 0a5b28c825f388ee4f3cb7f7036ac9988aa3bf6653c8d3a7a0794d1beaedec0c
font_03_sfnt_off00011b37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B37 16524 bytes
SHA-256: 93205af88e9b14cc4b55842f1a1dbaec9dd747c448e4a683240cced0c0ce23a7