Malicious PDF — malware analysis report

Static analysis result for SHA-256 2098a3bf65a68e33…

MALICIOUS

PDF

84.9 KB Created: 2021-08-13 03:13:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: c162f455e07dbf74a4e20bdc8bdb9a58 SHA-1: bfffc747ab2204ec140783df034bc8645e22f5eb SHA-256: 2098a3bf65a68e33ea1f1ba3af434bb36539365ec12c4df2114adff1320b7cda
164 Risk Score

Malware Insights

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

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 and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/de6fd24f2537244c5984e7cee24859b7/diwako.pdf In PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/lejijamilujuzizukud.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/edd4cf37876acfbf773ad1cec0a4a9e1/nagiwolelazedisimolu.pdfIn PDF document text
    • https://toocapen.com/files/93445130.pdfIn PDF document text
    • http://pillshop.ru/uimg/files/84705690085.pdfIn PDF document text
    • http://womenscouncildallasarboretum.org/clients/85748/File/jusonawipisazotigopakul.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/96625116754.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c03f3d8121---60023101382.pdfIn PDF document text
    • http://aaronandanthony.com/userfiles/files/lavik.pdfIn PDF document text
    • http://brilspa.ro/userfiles/file///13762702489.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/t9a538pifcrl037vcol7erv08h/31167523434.pdfIn PDF document text
    • https://brahmagnanam.org/fck_uploads/file/gamofuvo.pdfIn PDF document text
    • http://arlingtonhigh1960.com/clients/881088/File/mijone.pdfIn PDF document text
    • https://diaochue.vn/userfiles/file/sopesovod.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/7a5002ff2b611ae64a591ef8329266ac/94088274523.pdfIn PDF document text
    • https://etimes.mn/uploads/files/maxefakiduwes.pdfIn PDF document text
    • http://greatnice.club/updatefiles/file/guwezenibajufo.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/24389561dc298e8d442ae313dc970756/sazeberit.pdfIn PDF document text
    • https://kabelkyaobuv.sk/editor_uploads/files/42687730069.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=nokia+130+flash+file+downloadPDF 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_off0000e8b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B7 17304 bytes
SHA-256: f420cd31b4e9923b10b5070d785b86433fbd93a134bb257d614c074da9f1d24f
font_01_sfnt_off00011561.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11561 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D78 10756 bytes
SHA-256: 0e2ca5944337550d5aa709f510f945f1ecf44562d4d045a1916048166cb76c32