Malicious PDF — malware analysis report

Static analysis result for SHA-256 19c9cb9d1dc48058…

MALICIOUS

PDF

76.2 KB Created: 2021-09-19 09:53:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 04801d912d3d51ad163c4198d6ddbdf5 SHA-1: 95e3b27bda24f268ab940202e8680c69e0e52d8c SHA-256: 19c9cb9d1dc48058910da521bc62ef5f1359ad5b08e226cc154a8fb4b583c1fa
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV. It contains numerous external URIs, many of which are hosted on disposable domains, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using many distinct hosts with few links per host, a common tactic for evading detection and distributing malicious content. The presence of embedded URLs further supports the attack pattern of redirecting users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://smidgel.ru/uplcv?utm_term=barron%27s+sat+math+level+2+pdf PDF link annotation
    • http://goteneplast.se/files/images/file/nibolimuzorutuxalo.pdfIn PDF document text
    • http://dryoucosmeceutical.com/userfiles/files/taxanubiwixaxafuf.pdfIn PDF document text
    • http://aaykpn.com/uploads/editor/files/kuwew.pdfIn PDF document text
    • http://olympusflights.com/files/files/33965790515.pdfIn PDF document text
    • http://onyx-innovations.com/assets/ckfinder/userfiles/files/25669456572.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130088bbf297---76908353916.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/lodapozawebokosiwopeta.pdfIn PDF document text
    • http://hanarotalk.com/userfiles/file///jodopipanobopokoni.pdfIn PDF document text
    • https://tahubunting1.com/contents/files/81424070810.pdfIn PDF document text
    • https://unitytradecapital.com/ckfinder/userfiles/files/sugubil.pdfIn PDF document text
    • http://4bx.pl/public/file/95034364023.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/wugiloxovikukiduvaboxuzin.pdfIn PDF document text
    • https://cuacuonbentre.com/upload/files/sajesagadunol.pdfIn PDF document text
    • https://francemonde.news/UserFiles/file/22383150367.pdfIn PDF document text
    • http://elateridae.com/images/FCKeditor/file/saloxusijirejibirogol.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109061114504932.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/2809630847.pdfIn PDF document text
    • http://ski-experience-japan.com/images/blog/file/zemekasatije.pdfIn PDF document text
    • https://www.milestonesmn.org/ckfinder/userfiles/files/memamedidarogijozare.pdfIn PDF document text
    • https://promoxcenter.ro/ckfinder/userfiles/files/70474259603.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/69227899291.pdfIn PDF document text
    • http://zubrcup.by/files/files/20659437098.pdfIn PDF document text
    • http://parateam.cz/file/vinesowa.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/xebupexex.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_off0000c5e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5E4 17028 bytes
SHA-256: df24fa8dd8fe5579cfcef855b490a0e8ea1ad15804e76a60efaec89fc61736a1
font_01_sfnt_off0000f1d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109EC 10944 bytes
SHA-256: b2635d474dcc2ff2f2aea6726c071db53066481ada26f2256eb7a272fab31279