Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7e4db9fe2fd5c84…

MALICIOUS

PDF

80.5 KB Created: 2021-09-08 14:22:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 69811f9659cc60b1da728e4b829db84f SHA-1: 2709f8db900cf803590bd95a0cc208c839e18475 SHA-256: b7e4db9fe2fd5c8453734918aa39b336547e08216f9d408a60d51186a5a28396
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high probability of malicious intent. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, characteristic of a link farm used for phishing or malware distribution. The presence of these links suggests the PDF is designed to lure users to external sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://ityab.com/cache/fck_files/file/76333563089.pdf In PDF document text
    • http://bubb.cn/up_file/file/wanifigovopuvotiv.pdfIn PDF document text
    • http://msiutilities.biz/documents/14616283415.pdfIn PDF document text
    • https://samsungdvmklima.com/upload/ckfinder/files/69583294283.pdfIn PDF document text
    • https://thefertilizerproductionline.com/d/files/sojunikuradiviz.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/b6065e036bca9f7429471f59994353ac/rasevalorebevaliviw.pdfIn PDF document text
    • http://4bx.pl/public/file/wuforiliwiwudoj.pdfIn PDF document text
    • http://weiken-rc.com/upload/files/ladidobofokumo.pdfIn PDF document text
    • http://jdjcnc.com/upfolder/e/files/20210902102554.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/072d5dc0511240830817b56f48470c02/xubizes.pdfIn PDF document text
    • http://consol.hu/images/uploadedimages/file/3500347348.pdfIn PDF document text
    • https://nevjegyzek.eu/uploads/file/53844774336.pdfIn PDF document text
    • https://cyklo-wellness-penzion-palice.cz/content/16782642985.pdfIn PDF document text
    • https://agroadvanced.com/app/webroot/newsletters/editor/files/6503395158.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16133f8749f872---89173552251.pdfIn PDF document text
    • http://studioghittigargnano.com/userfiles/files/99000279200.pdfIn PDF document text
    • https://aparcaderoshaddaichile.cl/uploads/images/files/dutopukazemegoxavipifume.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/lodemoso.pdfIn PDF document text
    • http://worldplastsolution.com/ckfinder/userfiles/files/bawufisumajazuz.pdfIn PDF document text
    • http://kernenshepler.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/ninugopofexaz.pdfIn PDF document text
    • https://grandhotelbulgaria.com/userfiles/file/23141227260.pdfIn PDF document text
    • http://parbatsamajjapan.com/img/files/files/87123030804.pdfIn PDF document text
    • http://erulingua.hu/uploads/content_files/files/16269548690.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/bf45063f974108d10978e1071db999e4/sosox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=insert+pdf+into+ppt+2013PDF 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_off0000d726.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD726 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3D 10700 bytes
SHA-256: afcfbfd4f5ecfd20b3c67333f6352252aa44bf2001726abfccf224a8130426cf
font_02_sfnt_off000107f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F7 17232 bytes
SHA-256: ba5293c75739c0921f7d34320f46e6e9dc72e9310a0fb71ac64d0180f6fe4543