Malicious PDF — malware analysis report

Static analysis result for SHA-256 d0f1ff88cd159ea7…

MALICIOUS

PDF

71.2 KB Created: 2021-10-02 09:19:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 70cfb2d449aca8c8045cfcf6a60837cc SHA-1: 3723a4d74fc45aba3d5247f39f99d22176a6c114 SHA-256: d0f1ff88cd159ea7ba5b60362ae747f927f641c9253b2b816fba18c572101c48
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a phishing trojan by ClamAV and flagged by an ML classifier. It contains embedded JavaScript and a large number of URLs, many of which point to compromised websites or link farms. The presence of JavaScript suggests an attempt to execute malicious code within the PDF, likely to redirect the user to a malicious site or download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://huntic.ru/uplcv?utm_term=100+oz+to+litres
    • http://altus.pl/userfiles/file/tidonomono.pdf
    • http://coinproject.com/userfiles/image/file/vewefamowonolijel.pdf
    • http://xn----ctbguteehkho5h.xn--p1ai/ckfinder/userfiles/files/pubixavogapu.pdf
    • http://skupka23.ru/upload/m/teliboze.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c9701711e0---527011763.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7c4655878---nezozajinezufafi.pdf
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/63586071665.pdf
    • http://ngocminhcnc.com/demo_thietbimay_24_7/upload/files/5825237940.pdf
    • https://smartcirclegroup.com/userfiles/file/22241434439.pdf
    • https://kirbas.com/img/uploaded/file/wabuzivalizutevoxezu.pdf
    • https://nikoljski.com/ckfinder/userfiles/files/namasoremu.pdf
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/98097333488.pdf
    • http://luijkzonwering.nl/image/file/bufejedodoxulasifuveroka.pdf
    • http://builderall.info/userfiles/file/60647347850.pdf
    • http://garage-fuji.jp/js/upload/files/30650782058.pdf
    • https://anakaygame.net/calisma2/files/uploads/zovufinom.pdf
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/6ce7e36058d4fef399f117d30feb5ffd/96876245187.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/gmb47s64jbd4iuhu3m1cmv7frm/23295672731.pdf
    • https://ctsgroups.asia/images/file/80870300651.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/1612fcb176220f---kazuposiwi.pdf
    • https://thietbidiensino.vn/media/ftp/file/mewipar.pdf
    • http://matrixpaint.com/ckfinder/userfiles/files/jawifiwinus.pdf
    • http://ardennes.proximeo.com/ckfinder/userfiles/files/96281156925.pdf
    • 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_off0000b4a3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB4A3 16792 bytes
font_01_sfnt_off0000ccb9.bin
bb0be5ee23145a82ac6df87d7b874adc69eded309de7e0ecfcd9a422d83144e2
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCB9 9972 bytes
font_02_sfnt_off0000e2f1.bin
c4b02cfc3aee924228b53ec1456f8d372aa124536edbc6d78f407ae3c9292bed
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2F1 17308 bytes