Malicious PDF — malware analysis report

Static analysis result for SHA-256 9108fc4427c295b6…

MALICIOUS

PDF

84.9 KB Created: 2021-07-20 01:13:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4f8b0e7e07d5b4a58a31c31bc0fc3d08 SHA-1: 47a4a2e81ea207eb7dbef3c48d4f0c845f3679e5 SHA-256: 9108fc4427c295b60dce37de641552670a27c8c58c140fe7887228b52ea710a2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs, several of which point to compromised CMS upload directories. The ML classifier and ClamAV heuristic strongly indicate maliciousness, classifying it as a phishing trojan. While no scripts were explicitly extracted, the nature of the link farm suggests an attempt to direct users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://africanresearchcenter.com/userfiles/file/lubebonitixutabo.pdf In PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/jujakowumusanariba.pdfIn PDF document text
    • http://skipjackpoke.com/ckfinder/userfiles/files/tukina.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160993ef07e548---mababe.pdfIn PDF document text
    • http://liubeauty.com/luutru/files/vepimiv.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/nrf89qpk6a0pkrcejtu0d88v81/25165768440.pdfIn PDF document text
    • https://chaletsuenodesol.de/files/7956066402.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/38pgq91rcve3k5avtj371o33j2/nojega.pdfIn PDF document text
    • http://stalmost.pl/userfiles/file/14421296350.pdfIn PDF document text
    • http://churchillreunion.com/clients/72216/File/55217818925.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bba5fe66c8f---japozibenebeziw.pdfIn PDF document text
    • https://izr.fr/files/rusidekesa.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607750c456787---93363516858.pdfIn PDF document text
    • http://hongdanhaudio.com/luutru/files/9781631900.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/8b73m1a3ec1t0du4jg0giosep0/13870160576.pdfIn PDF document text
    • http://www.kymenhome-etsinta.net/tiedostot/files/valaxugimerovifugezuduwo.pdfIn PDF document text
    • http://bidmitt.com/img/files/file/22760801026.pdfIn PDF document text
    • http://10glazsikeyrosa.ru/file/77706016021.pdfIn PDF document text
    • http://bociany.sk/media/file/78659687696.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608d8eaee30a8---ridumiz.pdfIn PDF document text
    • http://bortran.com/upload/image/file/20210530122045.pdfIn PDF document text
    • https://office-agglo-larochelle.fr/userfiles/file/14146060423.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=compare+and+contrast+sound+waves+and+electromagnetic+wavesPDF 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_off0000e5f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F0 11140 bytes
SHA-256: 4b7b172f8dd8c84e5ba902972ecf4fda03e41f993b20ca437917f3fa9db99669
font_01_sfnt_off0000ffcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCC 17516 bytes
SHA-256: 15761f42ea99bcc7bd3e67a57e420d8cbaace261aa30619793681b8c087eff30
font_02_sfnt_off00012df0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1