Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d8a62d7f9f4cee3…

MALICIOUS

PDF

79.2 KB Created: 2021-09-19 05:03:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 68a5d668d9cf831ba2789d9bac838605 SHA-1: 844e71bf6965c466422c98c69696a392fafaa36e SHA-256: 6d8a62d7f9f4cee3dd4e94dfcf4c1cdebf3f76df84cd9df9d7d553d3e37c35cb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to other PDF files, indicating it functions as a link farm. Several heuristics suggest these links are hosted on compromised WordPress sites or disposable hosting, increasing the likelihood of malicious intent. The ML classifier and ClamAV detection strongly indicate malicious content, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://medvor.ru/uplcv?utm_term=my+cat+android PDF link annotation
    • http://fcraregistration.com/UploadedData/file/nekida.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/41883203146.pdfIn PDF document text
    • http://metamorfoza-krosno.pl/userfiles/file/pideminarofafununona.pdfIn PDF document text
    • https://standsimulator.com/ckfinder/userfiles/files/64615292470.pdfIn PDF document text
    • https://towa-aaa.jp/userfiles/file/revuvudaguwolivetipozavup.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614146e5d6e78---95344013175.pdfIn PDF document text
    • http://gazdalkodjokosan.hu/img/userfiles/file/romisosova.pdfIn PDF document text
    • http://bajkolandia-leszno.pl/userfiles/file/49431673384.pdfIn PDF document text
    • https://koratspring.com/upload/file/pesazukulelewi.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/dopodomovix.pdfIn PDF document text
    • http://www.moyekolodin.com/files/lewevapuloganased.pdfIn PDF document text
    • http://ambulanceservice.pl/userfiles/file/magamoxojenisixoju.pdfIn PDF document text
    • http://koala-al.com/d/files/73475447576.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/1iv20hl6qdes11qluh6c8gr97c/75097501939.pdfIn PDF document text
    • http://proleague.dk/userfiles/file/70826938637.pdfIn PDF document text
    • http://chixue.com/uploadfile/file/20210905014908.pdfIn PDF document text
    • https://hmradiatoriai.lt/images/files/jububaguseminaxapafopojez.pdfIn PDF document text
    • http://icaalliance.org/filespath/files/20210905063409.pdfIn PDF document text
    • http://dorp.pl/userfiles/files/9667628859.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/f633d9dc058a6bcf8b3ae00386783508/vekutoxoxixowod.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_off0000d251.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD251 18112 bytes
SHA-256: bd319fb6bf0c184f300e2181d59ae49ed981e43c24caf5de8b895de5bcdd5432
font_01_sfnt_off0001012e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1012E 10124 bytes
SHA-256: 70acfc97ffffa051841d1fef023f3fba70e701e26290f9426b3f9d2c7968e79f
font_02_sfnt_off000117ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1