Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5277dcc2b5e930d…

MALICIOUS

PDF

83.9 KB Created: 2021-09-23 08:12:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: f0241001b4dc29f1c29d4ed67151ff89 SHA-1: 50fd3bc32fb8814ed71d37bb1d07ad27ec46d4ec SHA-256: b5277dcc2b5e930d72c987a160d3af4b50989333d8c8495003086b801a264448
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution scheme. The presence of PDF-specific heuristics further supports its role as a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://laborke.ru/uplcv?utm_term=hyperglycemia+vs+hypoglycemia+symptoms+chart PDF link annotation
    • http://kodemari.info/data/files/44097048415.pdfIn PDF document text
    • https://mygenius.ru/admin/ckfinder/userfiles/files/15244322886.pdfIn PDF document text
    • https://godahoian.com/app/webroot/upload/files/93758308871.pdfIn PDF document text
    • http://zjnep.com/ckeditor/ckfinder/userfiles/files/97910124679.pdfIn PDF document text
    • http://kammerchor-lindau.com/file/69856494266.pdfIn PDF document text
    • http://makesomenoise.hu/upload/file/47815165370.pdfIn PDF document text
    • http://onlineticketreview.com/images/file/fusimagugivirovose.pdfIn PDF document text
    • https://24emk.ru/ckfinder/userfiles/files/rewubenozidedezefuwu.pdfIn PDF document text
    • http://kpghomerepairs.com/uploads/image/files/baxim.pdfIn PDF document text
    • https://senfina.top/uploads/files/toxiwaneruvekikewufuku.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021091204574473499.pdfIn PDF document text
    • http://predit.ru/admin/ckfinder/userfiles/files/dedudaweberakobamusagu.pdfIn PDF document text
    • https://banderlogclub.ru/Files/file/40281605520.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/pevesuxivodojukabiguvafiz.pdfIn PDF document text
    • https://peoplehelppeople.net/uploads/File/geporupulenuvus.pdfIn PDF document text
    • http://ordinate-ltd.com/file_media/file_image/file/wuxakez.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/9e3387800cac89b2132dd66dd8b3e398/wesinimalubudovo.pdfIn PDF document text
    • http://dienlanhtruongson.com/upload/files/pufezagexetokutoda.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/61914874436.pdfIn PDF document text
    • http://2478.ru/admin/ckfinder/userfiles/files/52639105920.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090520273056.pdfIn PDF document text
    • http://appli-veolia.net/ckfinder/userfiles/files/77034679477.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/4743ac389f729793b158bda49fd3639c/34004785230.pdfIn PDF document text
    • https://rugsdirect4u.com/uploadedfiles/file/gadubixebivovesibasixezuw.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_off0000e095.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE095 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A7 18212 bytes
SHA-256: 3a866f626041dabccb1e73b4c2b5f01b4b0d17152674950b9bd116720a3de724
font_02_sfnt_off000127fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127FA 10888 bytes
SHA-256: b45336ffc3fd6afc53a0b0f440a23f82e03c45669067ccbf0bc3271cad85b7cb