Malicious PDF — malware analysis report

Static analysis result for SHA-256 4423f6804a6b6e5f…

MALICIOUS

PDF

98.1 KB Created: 2021-07-19 02:46:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2e85dff013bb96eb6dfa88fb18ff60f5 SHA-1: 981df81e3325ee6820633067cc2272af1651c617 SHA-256: 4423f6804a6b6e5f2f122907d6c3c0889128092562d0eb44055ad5b3581a96d3
156 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a link farm with numerous URLs, many hosted on compromised CMS platforms or disposable domains, suggesting an attempt to distribute phishing content or malware. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://urparitet.ru/admin/ckfinder/userfiles/files/34921124544.pdf In PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/8af7b096085efcddf9d7be5b27f2a70b/15432738142.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/fffd37f1a2500d11c09d75fee9c2cb21/tarel.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/pnuh2ka5tktsdk27rnghtdc59s/jivodamotafap.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096fc67b5dd8---67680763795.pdfIn PDF document text
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/69037301027.pdfIn PDF document text
    • https://cafesca.info/ckfinder/userfiles/files/22040278295.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/12c77e810c740d9f227f439c26d90ace/74291756555.pdfIn PDF document text
    • https://autoprofi.ua/userfiles/file/vuxotedotabujize.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aa04503b00e---tafifusojax.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/lasojenafodekidivoxex.pdfIn PDF document text
    • https://sport-jicin.cz/dokumenty/tekuxasivemodubopizipo.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/gogupurotavunadonipunaxo.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a43f909c398---zizezixonedipafiwukuk.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/5m705b8r2bifrvr4nqdb4i2s4n/31868384501.pdfIn PDF document text
    • https://pbchistoryonline.org/uploads/file/15935949202.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/putebozega.pdfIn PDF document text
    • https://mediaget.ru/userfiles/files/1275739336.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607a377963969---sikerediponi.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b29ff4a7723---7678521431.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/bf1747b7dfe4341034dbc6c28da104d9/duvol.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/16080253aee356---46549030429.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a110853eb7---90064375948.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adc42d0b038---78540948699.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=get+well+soon+smsPDF 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_off00011f5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F5F 17056 bytes
SHA-256: 29205d6f28e234756c6ca4b66fd6dc19564075766b88044420054aca1a41ffe6
font_01_sfnt_off00014ba7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14BA7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000163be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x163BE 10040 bytes
SHA-256: e63fb1b9c5c83628381578a69b83095bcfafb14b396ac069a8ff0367d74a3d71