Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f5c210df9945f61…

MALICIOUS

PDF

91.7 KB Created: 2021-07-01 23:17:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 76f4b03f8d9830a0e752eb920f0f0c07 SHA-1: ad6d709cda72e1d8ac82c7f0b7ef063788a798b6 SHA-256: 4f5c210df9945f61a6ad936092142ce49c27bfc758f461142dc32ce0717fbc11
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm with numerous URLs, several of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the presence of multiple external links and the detection results suggest it's designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://www.aqsclimited.com/EditorImages/file/59343010318.pdf
    • http://gtlmarinefuel.com/userfiles/file/54514822630.pdf
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a3943fdb06d---damowumapisoke.pdf
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/ec07878b01dbf8d2945a2edfb23527d0/40936949960.pdf
    • https://marwaautorepair.com/nbloom/fckuploads/file/88374379885.pdf
    • http://mikailang.net/userfiles/file/20210506210409_924018493.pdf
    • https://best-label.com/upload/files/bemabefijelajeve.pdf
    • http://kimhoatra.com/upload/fckimagesfile/90363115926.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a086fb35e6f---77956282944.pdf
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/3a6334c194943c099d3c6caab7587d94/neviko.pdf
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/4b94bc8ef2892430d347ce7a057e7713/47770482197.pdf
    • http://yule-sign.com/upload/editor/file/20210614041403.pdf
    • http://ourhkg.com/UPFILE/userfiles/files/35154076244.pdf
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/t9gm6nr50q66lnad5ppi0c9vk2/luxab.pdf
    • http://liubeauty.com/luutru/files/85985055938.pdf
    • http://hz-karavany.cz/ckfinder/userfiles/files/verubikukepel.pdf
    • http://erictex.com/ufiles/files/poduzefofukuke.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/b0088769d32b8b36ae3ef4c8a6018280/25205564056.pdf
    • http://technoculture.cz/admin/upload/file/78708149866.pdf
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160761bbc0d742---budafisu.pdf
    • http://1960vonsteuben.com/clients/d/df/dfb5e1b83ea85bfdc5ef1da934264264/File/49506330823.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=malcolm+in+the+middle+online+episodes
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000105d4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x105D4 16792 bytes
font_01_sfnt_off00011de6.bin
bdf87ac3cd421bd06fc6447fe5ce47dbd5296c3c95438a748c10eb408b2de81f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DE6 16768 bytes
font_02_sfnt_off000149b2.bin
650e79fb42644651b3bcfb5775458c75a4f28b874b6c31634152d0e7484ad25a
pdf-font-stream PDF embedded font (sfnt) at offset 0x149B2 10672 bytes