Malicious PDF — malware analysis report

Static analysis result for SHA-256 812b7889355de4e8…

MALICIOUS

PDF

71.7 KB Created: 2021-09-17 05:56:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 60c467c156459eee734d1086b0975e6c SHA-1: 84e27406b2d634942e989439d9771d1f2e7205a2 SHA-256: 812b7889355de4e8ead2973e54cad3df728296fbb2fbd97c94bef632790da7b5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to disposable hosting, characteristic of link farms used for phishing or malware distribution. The PDF structure and embedded URLs suggest an attempt to lure users to external sites, likely for credential harvesting or further infection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://synerhu.ru/uplcv?utm_term=samsung+galaxy+s3+papierkorb+leeren PDF link annotation
    • http://lev-steklo.ru/userfiles/file/81622671073.pdfIn PDF document text
    • http://dongsimkindergarten.com/upload/files/puxodoxupadi.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/73525521553.pdfIn PDF document text
    • https://zenithoverseas.com/assets/userfiles/files/24143950064.pdfIn PDF document text
    • https://go2germany.ru/files/file/pomaxegoruviwenisepixaj.pdfIn PDF document text
    • http://celesteandtorsten.wedding/images/file/jubesupuzur.pdfIn PDF document text
    • http://31kouqiang.com/userfiles/file/1630803774.pdfIn PDF document text
    • http://tuning-zone.eu/userfiles/file/50716997170.pdfIn PDF document text
    • http://revistaspontan.ro/assets/ckfinder/core/connector/php/uploads/files/gagosa.pdfIn PDF document text
    • https://linardi.ru/files/file/wadaxuz.pdfIn PDF document text
    • https://nmcs.ca/userfiles/files/67681919933.pdfIn PDF document text
    • http://euro-ex.net/images/blog/file/59283250512.pdfIn PDF document text
    • http://ags-sib.ru/ckfinder/userfiles/files/6194990615.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/dirijelidos.pdfIn PDF document text
    • http://originalavto.ru/userfiles/file/bivege.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/rowarigokugabe.pdfIn PDF document text
    • https://jungleflightchiangmai.jungle-flight.com/Uploads/files/rokigof.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143618a8fb06---47254008271.pdfIn PDF document text
    • http://teamtrinity.net/trinitya/file/gowakufipujojejonitak.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/aee5a59eb09a61bcc94f04fd8b1faa58/27512049481.pdfIn PDF document text
    • http://www.yt333.com/userfiles/20210911/file/1631316729.pdfIn PDF document text
    • https://cryptoshift.be/anaeter_capital/siteadmin/userfiles/files/73425949258.pdfIn PDF document text
    • https://usssecuritate.ro/userfiles/file/lijuvolipedegitiza.pdfIn PDF document text
    • 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_off0000b208.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB208 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA1A 17448 bytes
SHA-256: f935ee5f4883bc240af9138dc770642d2e9b1f16b78fd5e53b24cdf67ce4f71e
font_02_sfnt_off0000f5b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B1 11292 bytes
SHA-256: 6abd86597df7fbd9328433f5b3976e19500eede5513750776da5d43c80d2f794