Malicious PDF — malware analysis report

Static analysis result for SHA-256 a23f44afaa6a9dcc…

MALICIOUS

PDF

84.1 KB Created: 2021-06-25 17:47:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: b2703722a9566a6b8156a05a142ae1e5 SHA-1: 23758283213260baad506ddc6ffcdb6baf649889 SHA-256: a23f44afaa6a9dcc48a7faf500d8141ab474182f435bbe3913a25a47737aff55
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many pointing to compromised websites or disposable hosting, characteristic of a link farm used to distribute malicious content or phish for credentials. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://tamlaproject.com/userData/board/file/kefopafekesujitiwotux.pdf In PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/wujunapa.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/2b7d452a3206bc5cce1f6c4f0a91126a/gurowalezawubi.pdfIn PDF document text
    • https://actor-conseil.com/files/file/26298490110.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e331f9864a---79743458319.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c8cc105c3---sumeluwukonisifeparu.pdfIn PDF document text
    • http://dogable.de/userfiles/file/93363537973.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/j7folmj9st2o9nip1ho70nfaso/xizojititamanifukus.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160c58900b33b3---79369032785.pdfIn PDF document text
    • http://meadescafe.com/userfiles/file/63350835285.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8aec9e52d---merakajanebobimepituxapun.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/53j8ml6a7gaule0i7b6kj43l2u/murakigigukuzope.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096e4f315f07---bosonejeresitomagexuror.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/zaxunuzin.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/e208009dc5e8caf41e189e3e7fa684be/30423507991.pdfIn PDF document text
    • http://the100voicesofgospel.de/fichiers/newsletter/file/wegumupuvonudipowuk.pdfIn PDF document text
    • http://aep-tc.com/cache/fck_files/file/6306037990.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/85130221419.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/j1oe3gaelkh58chqqtqqa6il8m/34132295013.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a46029ab3---nuxilewuzikixuxurovefa.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160779d2c52ef0---24301523591.pdfIn PDF document text
    • https://sheenabusesandcoaches.com/userfiles/file/nifewinunurifagitadiwox.pdfIn PDF document text
    • http://caigeshi.com/uploadfile/file/2021060809513373499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=thank+you+from+the+mountainPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce03f53eb4---19542606969.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_off0000e4ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4AC 10536 bytes
SHA-256: 7af035b5ccdd86f4f8a3356349a0e1c051af222f229a4b0442cc91ac51e1d890
font_01_sfnt_off0000fc82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC82 17756 bytes
SHA-256: 937a735e51e66918e42bc6aeb22f83b31497221472df6fa2b5fedb51746b7267
font_02_sfnt_off00012af9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AF9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1