Malicious PDF — malware analysis report

Static analysis result for SHA-256 516f862adf888a4a…

MALICIOUS

PDF

72.5 KB Created: 2021-09-17 12:28:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e1d9d0931611e620d114260fe166435f SHA-1: 37bb999aa881d316f1752d19e0a99b97606fb973 SHA-256: 516f862adf888a4a4f296c6dab05f4d601a8e1236fd153e66c71e68f3b8021a9
126 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 identified as a phishing trojan. Heuristics indicate the document functions as a link farm, containing numerous links to disposable hosting, suggesting an attempt to direct users to malicious websites. The document body is heavily obfuscated and unreadable, providing no direct textual clues to its purpose beyond what the heuristics reveal.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://sacc-la-chaux-de-fonds.ch/fichiers/file/jumizanora.pdf In PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/71212572498.pdfIn PDF document text
    • http://balaton.varosom.hu/userfiles/files/rokeminipizukowusaxodizef.pdfIn PDF document text
    • http://idealthailand.com/file_media/file_image/file/58070063689.pdfIn PDF document text
    • https://mehfermobilsaglik.com/userfiles/file/genamufokedalarapuzi.pdfIn PDF document text
    • http://villkasz.hu/editor_up/94608310350.pdfIn PDF document text
    • http://henzefashion.com/userfiles/file/96432662886.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/ded757e9759466f410037061b42c0f63/luwasezuxawamazavel.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/77725503233.pdfIn PDF document text
    • http://vector-food.pl/userfiles/file/dobewadurosepefa.pdfIn PDF document text
    • https://vadihosting.com/calisma2/files/uploads/xodapadisozepuruv.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/xodutapo.pdfIn PDF document text
    • http://express-service-auto.fr/ckeditor/ckfinder/userfiles/files/75475120271.pdfIn PDF document text
    • https://altstudio.be/app/webroot/uploads/file/81069672093.pdfIn PDF document text
    • http://nut-shell.net/upload/files/ranixesonor.pdfIn PDF document text
    • http://stavo-bazar.cz/userfiles/file/29547199132.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161323969017a0---divekagivid.pdfIn PDF document text
    • http://qianshunqs.com/admin/upload/93294910852.pdfIn PDF document text
    • http://arabic.cz/ckfinder/userfiles/files/fokorafamavamex.pdfIn PDF document text
    • http://allineers.morefriendship.com/upload/files/wejosavekuwupulevavipam.pdfIn PDF document text
    • https://dreptultau.hotnews.md/upload/userfiles/files/24276434107.pdfIn PDF document text
    • https://dom4m.lv/userfiles/files/tiwupubirovapufixovubilof.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/fudaruvawolerebeluvem.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/vutisobafodag.pdfIn PDF document text
    • http://bxbrdh.marketsearching.com/upload/files/71373560250.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=do+android+phones+automatically+change+daylight+savingsPDF 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_off0000b73d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB73D 16508 bytes
SHA-256: 5cc50d9f16a1f3b613e8b9ac67cc662ce0b066f9a9e660a7dccaa99eaf979f27
font_01_sfnt_off0000e180.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE180 11240 bytes
SHA-256: 95ff25569233016f82e89ecd07be611fdb4b9c1b7085ac390e294ef273b1bf89
font_02_sfnt_off0000fb7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1