Malicious PDF — malware analysis report

Static analysis result for SHA-256 b930f5accfdb4203…

MALICIOUS

PDF

81.3 KB Created: 2021-09-06 13:06:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 55d185ee8e2118d96add563c40190404 SHA-1: 538a43ef2f65cb54afb514e717cd76f2f118820e SHA-256: b930f5accfdb42030e905455afb44ea204c53d414128fa6490f406bff1aa5e0e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a significant number of links pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://ovalpolycoats.com/media/musevumusovumizavoliv.pdf
    • http://maiodi.com/userfiles/files/4754262792.pdf
    • http://oio.cn/uploadfiles/files/76553170061.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078d29e902f9---fotufasi.pdf
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/amn663q492l5qo6r0aqr74egj5/83831692823.pdf
    • http://mulroyenvironmental.ie/userfiles/file/piwenozer.pdf
    • http://stavclearing.ru/upload/files/sagujirit.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/jitokimapogugepoxi.pdf
    • https://wildarium.com/ckfinder/userfiles/files/zimidutozutozikopo.pdf
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/161084a93f41d1---madofixaworemowikomop.pdf
    • http://www.hangmandigital.com/files/file/32227948058.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/1611c78cbb92d5---76988681689.pdf
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/f834cc6bfe920e6d00dae9939bdfe5dc/nitiw.pdf
    • http://dienmaythanglong.org/uploads/files/wodadanatoresapirujosos.pdf
    • http://kimhoatra.com/upload/fckimagesfile/jusikozupefusugafilutu.pdf
    • http://dighakanchaninternational.com/FCKeditor/file/54453056135.pdf
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/ade89df433d1ca11968d46c59c5a24e4/68857844956.pdf
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608af0b077e5a---53856403148.pdf
    • https://nestaerospace.com/uploads/file/wepadefixoparifelupe.pdf
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160e75e8a52e08---71593885765.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160836094111a6---74151235130.pdf
    • http://presssimayeshahr.ir/pic/file/94709117625.pdf
    • http://laros.cz/UserFiles/file/63897501913.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=linux+tutorial+pdf+in+tamil
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce09.bin
6aece02a0476668957c433c60d733bf9f3dab59b5fadc7028d93db2d41b97b55
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE09 10520 bytes
font_01_sfnt_off0000e5eb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5EB 16792 bytes
font_02_sfnt_off0000fdfd.bin
0f9840663e5352544d613d0f68853a3eb6fe46101f6b96057ad38e57bc2a197a
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDFD 22364 bytes