Malicious PDF — malware analysis report

Static analysis result for SHA-256 a437be0b8c8ae91e…

MALICIOUS

PDF

78.5 KB Created: 2021-08-28 16:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 0fb7881bf19f3dae31f13fc0e532dea6 SHA-1: 1b397f4be95007fe1ba2f225d35ff744e1ec7b23 SHA-256: a437be0b8c8ae91e19e40a53abaa9623b81b0cc60b329e033d43d56d80e675b4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://catamma.ru/uplcv?utm_term=how+to+cut+a+part+of+pdf+page PDF link annotation
    • https://clubforeducation.com/FCKeditor/userfiles/file/61279872046.pdfIn PDF document text
    • http://thoitrangvabaoho.com/Images_upload/files/67104985420.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/otpdd8g33gu13np65s8svvukd0/wibofamekagejewefogut.pdfIn PDF document text
    • http://df-2.de/images/daten/file/tekinozujiv.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160f3c747e470a---81795914766.pdfIn PDF document text
    • http://xn--hy1bt45apoap01a.net/jangheung/userfiles/file/49529909850.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094dbbf04b09---tenasinikibo.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/re0p6cr3amol8iumq0rqbq447p/rekaradoxukodab.pdfIn PDF document text
    • http://ahchala.com/img/file/nitafamuruzujinisozegit.pdfIn PDF document text
    • http://solarexperten.ch/fckeditor/editor/images/file/tijaropatexemudimavusani.pdfIn PDF document text
    • http://massimosusto.eu/userfiles/files/19827253884.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ff6c0122b91---siluxelapogaselef.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/36281959274.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/87677312914.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/1ccfbf7978ab348b28a7496f40d1f584/27027292143.pdfIn PDF document text
    • https://amadesafar.ir/basefile/amadesafarir/files/68570691247.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/mg6oqso3bv5cegv3m1qdvvt145/35905755505.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2bc265477b---94774428533.pdfIn PDF document text
    • http://sammyuriasproperties.com/userfiles/files/69486435770.pdfIn PDF document text
    • http://we-women.de/default/files/uploads/file/pabivosadexomokoke.pdfIn PDF document text
    • https://rdsdealers.com/ckfinder/userfiles/files/96621604041.pdfIn PDF document text
    • http://grandinspirations.com/clients/75274/File/7614514967.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_off0000cfdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFDB 10560 bytes
SHA-256: 515b5d403c57e11536c4afee55603275990a8a841cb19bec27aee1542f70af7b
font_01_sfnt_off0000e7e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E8 16796 bytes
SHA-256: bfa6dd8c3711dcf6de4be904c8193b1a4d603c330f887494d1ecb6493c3cf1bf
font_02_sfnt_off0001133e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1133E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1