Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bb46ae937f6e81a…

MALICIOUS

PDF

73.0 KB Created: 2021-10-05 08:11:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: c6861d469d7152b11f434b9c2e95a8a1 SHA-1: 7a0a814d2b10c6c69b5626a195a48f9fe1f515a1 SHA-256: 9bb46ae937f6e81acc5d85112969a61e79ec747a53234fecf8d164b98eb09542
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous external links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://catamma.ru/uplcv?utm_term=hc+verma+chapter+5+solutions PDF link annotation
    • http://tuivaivietnam.com/uploads/files/mujulaletija.pdfIn PDF document text
    • https://khabul.mn/mmpa/userfiles/files/53538363825.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133115db769b---water.pdfIn PDF document text
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/56662272473.pdfIn PDF document text
    • https://searches.onlineconvey.com/userfiles/file/pedexubemufofoxab.pdfIn PDF document text
    • http://apsencollege.org/test/fckeditor/file/54971212325.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210919_8548B0ED6F1D0908.pdfIn PDF document text
    • http://chip-chup.hu/upload/file/tadimimasijaduvakupodefa.pdfIn PDF document text
    • https://sledovani.gpshlidac.cz/www/userfiles/files/57545489944.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/dofosawuwufamalu.pdfIn PDF document text
    • https://hoakhanh.vn/uploads/image/files/wadajomaladotuzovolimow.pdfIn PDF document text
    • http://0985028898.kad.tw/kads/ckfinder/userfiles/files/vasudagadevanew.pdfIn PDF document text
    • http://rideco.hu/upload/file/vopagodosefumakodegipipur.pdfIn PDF document text
    • http://sushi-belovo.ru/files/92060545580.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/modudetiriravoruzugedajar.pdfIn PDF document text
    • https://sofupingame.net/calisma2/files/uploads/rejukiwigojobiwi.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/5bb16fb3c344d2114ff70dd0eab89bff/vemetosuv.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec6be64f65---83026929189.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/madelaf.pdfIn PDF document text
    • https://asi-filter.pl/files/file/16313242366.pdfIn PDF document text
    • http://infracsap.hu/files/file/90047641635.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/libosu.pdfIn PDF document text
    • http://xn--b1amishc2fb.xn--p1ai/ckfinder/userfiles/files/zigilagisipalebelikidabun.pdfIn PDF document text
    • https://fullprotec.com/ckfinder/userfiles/files/3851115586.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_off0000b93c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB93C 10928 bytes
SHA-256: 64ddb7acea62775d0ca3750f09fda04ced3549af3e7bddb127885c50f7f930c1
font_01_sfnt_off0000d263.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD263 17108 bytes
SHA-256: 6daeb01ed1d9e816e66fd81922b72afdfc0d6a865d011281fc6d93b35b38b92e
font_02_sfnt_off0000fde0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1