Malicious PDF — malware analysis report

Static analysis result for SHA-256 67c37fabc9923a5d…

MALICIOUS

PDF

85.1 KB Created: 2021-09-13 22:49:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2811a14469ddaac311e48751abc4e077 SHA-1: 06fd1ccf968e982ac37ca2ad584f1640008066e4 SHA-256: 67c37fabc9923a5d4f05e740dd6851c7a438d45537c229b4e3db3d34ddafdd1d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The embedded URLs, such as the one pointing to a WordPress plugin upload directory, suggest an attempt to distribute further malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://sanchariglobal.com/userfiles/file/sutomajaxeda.pdf In PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/35773636451.pdfIn PDF document text
    • http://yarpb.ru/pic/userfile/xupoledotewagosuge.pdfIn PDF document text
    • https://lesura.net/userfiles/file/70695298691.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/jp06cthd4bc7uleigeej8loob7/34510582936.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/vf1spg71c7vb0ae6e9hl4khif6/3685288301.pdfIn PDF document text
    • http://proximeo.com/ckfinder/userfiles/files/xosaxetuxar.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/55741846016.pdfIn PDF document text
    • https://yenhuy.vn/upload/files/69594479822.pdfIn PDF document text
    • https://taxfirma.com/userfiles/file/22307012669.pdfIn PDF document text
    • http://caffepontoni.com/uploads/file/zogaso.pdfIn PDF document text
    • http://ozgu-yapi.com/firma/files/wibuwilulokimijupepuji.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613c86bc1328a---21413288200.pdfIn PDF document text
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/24783573340.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16138b8a9b6d4d---wawenejipalomezonalas.pdfIn PDF document text
    • http://tiwtactic.com/userfiles/files/1582976519.pdfIn PDF document text
    • http://zzzwchem.com/upload/files/taxowonakigekesa.pdfIn PDF document text
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/26107960902.pdfIn PDF document text
    • http://bacsionline.net/userfiles/file/36353954926.pdfIn PDF document text
    • http://anhhuynoithat.com/asset/files/19388272555.pdfIn PDF document text
    • http://e-motyle.natura2000.pl/imgturysta/files/timokor.pdfIn PDF document text
    • http://a-b-i-s.net/layout/bilder/file/vexesewegawonoke.pdfIn PDF document text
    • https://keralatemples.info/ckfinder/userfiles/files/majixojikemuzagobewawaxur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=gta+v+download+apk+androidPDF 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_off0000e98d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE98D 17552 bytes
SHA-256: 5753b66eeb865c9de998b1a3b8e6e05828078e14ca455cf4236334bf11ffb0f6
font_01_sfnt_off00011702.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11702 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012f19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F19 10368 bytes
SHA-256: e39dd86ba6d6954b63309fe0bbad0c6159192074aa4dda47e7999690fbf104c3