Malicious PDF — malware analysis report

Static analysis result for SHA-256 235cf4fd8da9ff35…

MALICIOUS

PDF

70.7 KB Created: 2021-09-02 14:25:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 8318a46d5db1d22f01534f30c12b971d SHA-1: ca2b51fa34ed323dc120bf9b6dc3a4855f291cf7 SHA-256: 235cf4fd8da9ff3553638fd4e866010d114686b93f03f0496e1885923c7266f9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://archism.ru/uplcv?utm_term=place+value+chart+to+hundred+thousands+pdf PDF link annotation
    • https://octvads.site/js/ckfinder/userfiles/files/96555731853.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/40004714198.pdfIn PDF document text
    • http://montpellier-businessplan.com/mbp/upload/images/images/upload/ckfinder/lamojinamadavirifitojimu.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/52682352860.pdfIn PDF document text
    • http://olymp-kiev.com/temp/fckeditor/file/27200344539.pdfIn PDF document text
    • http://myucpb.com/userfiles/file/xazexupinelibenovi.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/rktlrt6fogu3c0tg2j0emi6jcf/49711690857.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/2c8708ffb24e76ea366d4a55cbc2de59/bugowefaxo.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611ea955643db---sowonufopomu.pdfIn PDF document text
    • https://baobihungphu.com/media/ftp/file/37381830440.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/78511283065.pdfIn PDF document text
    • http://traiteur-ribot.fr/userfiles/file/waladadevalojiniwulipe.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608650354c289---pividazepofutaserowutirex.pdfIn PDF document text
    • https://keepingscore.org/userfiles/file/38492911604.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2fd43afff---vumazetetob.pdfIn PDF document text
    • http://meta-min.com/files/62815503958.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a77115b3266---tusulanosobatijitosamere.pdfIn PDF document text
    • http://bienenaktuell.com/sites/bienenaktuell.com/files/file/webatefawi.pdfIn PDF document text
    • http://prestopc.it/upload/file/ripovopazufezunis.pdfIn PDF document text
    • http://yousefmaktabi.com/ckfinder/userfiles/files/gupetavufudunekum.pdfIn PDF document text
    • http://cancercareresearch.com/userfiles/file/turokumuji.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/76485279478.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/v9ek6kjp9omb9nisg93fer8df9/tenixelemoranomatudozuju.pdfIn PDF document text
    • http://www.ciesol.com/ckfinder/userfiles/files/53980135874.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_off0000b6d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6D1 10792 bytes
SHA-256: e8ef9562315084696bf26b204084cd02cd415a971fdc83d72f0c2c9b9f938c24
font_01_sfnt_off0000cfb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFB2 14712 bytes
SHA-256: b412b0d1c8f31a90e2a790b1adbf02f1924e1584da28442d300cf4e0295252a1
font_02_sfnt_off0000f4d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1