Malicious PDF — malware analysis report

Static analysis result for SHA-256 35f2fa2ec0321066…

MALICIOUS

PDF

88.4 KB Created: 2021-08-07 00:43:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 3eccae511bd966fc5a7a85a129518312 SHA-1: 18f0f3b10248aeea57ae70fcb261d14c6eb81b73 SHA-256: 35f2fa2ec0321066c143bed73494ae3a2c73bcce217b4d6d473c50ccfa22dc0d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document that contains a large number of links pointing to various websites, many of which are hosted on compromised WordPress installations or appear to be disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ed5d3448d---25748915598.pdf In PDF document text
    • https://educhina.mn/editor/files/jelemiwe.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/eaafda6940102eba87f67c7da33a3dc6/43668554843.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1606f62429151d---54203159969.pdfIn PDF document text
    • https://aonetreks.com/uploads/file/liwagon.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/0860c50c3e06a10702f9f3e66b766a7c/30292572645.pdfIn PDF document text
    • http://kovove-ploty-brany-zabradli.cz/UserFiles/File/joluwixixibejabube.pdfIn PDF document text
    • https://www.groupenahno.com/wp-content/plugins/super-forms/uploads/php/files/j4dvp3ritqvd9k463e770k2a10/43543695423.pdfIn PDF document text
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/5223jll5nrep1c2sirpiiser3l/loxujimugirevadopipu.pdfIn PDF document text
    • https://klairtransport.com/uploads/files/bodefavigazobezelakurilip.pdfIn PDF document text
    • http://fredericjean.net/oplusco/file/39438557032.pdfIn PDF document text
    • http://mea-travel.pl/userfiles/file/87726824847.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/niselupuxipegesexi.pdfIn PDF document text
    • https://arvikabc.com/images/uploadedimages/file/nulegiwa.pdfIn PDF document text
    • http://minuspk.ru/minuspk.ru/userfiles/file/50912053598.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/risp96eiv05kjahee1qo9upj50/35649810758.pdfIn PDF document text
    • http://gioiacompany.net/images/upload/file/pegozu.pdfIn PDF document text
    • http://lhs60to70.com/clients/3/32/32806278e47d7e4d905c37b1d6ebf04a/File/10022755196.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a26ddc60335---kekikariti.pdfIn PDF document text
    • http://purpledoorchurch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160705b1ed682c---zavanolesupudonanam.pdfIn PDF document text
    • http://antichigelsi.it/userfiles/files/67800809186.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/12116811882.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/ximifewabajenopawuxuw.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/3l714d55v2ibv62notsp2shbk1/wopagefuvigizusotes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=what+is+the+most+realistic+vr+gamePDF 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_off0000f689.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF689 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010e9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E9B 17244 bytes
SHA-256: 33b6d5f2b3956200b496c532f8cb6253d9b21289eb1fed6bc4e878c7b062dde6
font_02_sfnt_off00013bd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BD4 10632 bytes
SHA-256: 323ddcaf9949a0ca91a2b437e3538e5eb107df55a7992ddaa06f477d7048f95a