Malicious PDF — malware analysis report

Static analysis result for SHA-256 c442c837ff6eff45…

MALICIOUS

PDF

73.1 KB Created: 2021-09-18 02:48:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 441e6e106e07e7f2f5c59439f68cd1cd SHA-1: e7146b192279657251edefafe603300ef7440448 SHA-256: c442c837ff6eff456d4b7983acf8d85bcc22543e1f38539e0ca6c5bc520ca2db
156 Risk Score

Malware Insights

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

The file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external URIs and links to compromised CMS upload storage, suggesting an attempt to redirect users to malicious sites. The PDF structure and embedded links are consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://pistant.ru/uplcv?utm_term=watch+free+conjuring+3
    • http://licausi.it/userfiles/files/19667351854.pdf
    • https://xosobacninh.vn/webroot/img/files/tobolu.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/161362deb698b7---rikokiva.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16130caa0e6eea---vumawexixi.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138bf34a57ff---fatites.pdf
    • http://quincy.pl/ckfinder/userfiles/files/63383612292.pdf
    • http://sushiyaslo.com/uploads/files/gepijafikafabeninip.pdf
    • https://chuyennhakienvangvn.net/upload/files/11699143076.pdf
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135ca1c34d92---35971760388.pdf
    • http://kystar.net/filespath/files/20210909102818.pdf
    • http://ues-rb.ru/themes/ues-rb.ru/files/vunumuvifavorapepilav.pdf
    • https://dialogueinpraxis.net/files/docs/53826705876.pdf
    • http://mobydick-band.de/fckdata/file/xitusufewinipujizekupeg.pdf
    • https://armature.ir/cache/fck_files/file/4923697575.pdf
    • http://ls12368.com/userfiles/file/66529074642.pdf
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135163a83262---sizeximis.pdf
    • http://abwingsva.com/uploads/files/tifare.pdf
    • http://mudrberanova.cz/userfiles/file/87778824897.pdf
    • http://sm300159.agchost.com/userfiles/files/92619918071.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16140973da9d76---17646983101.pdf
    • http://backupcenters.com/userfiles/file/34816565196.pdf
    • https://childprotectionindia.com/lexcyberia/userfiles/files/nitesisukanefulim.pdf
    • https://suacuacuontoanphat.com/upload/files/juzelajiniroxodepi.pdf
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/dendag2hq77dbbsdvqt373nup3/69153095029.pdf
    • 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_off0000b83b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB83B 16792 bytes
font_01_sfnt_off0000d052.bin
9b39922c50dd4ee75584f447afc176808ac72577e0933257d9a8e857421717c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xD052 10796 bytes
font_02_sfnt_off0000e934.bin
04501c8d2ef69d497822904fb573d80201d119e9c800b3732b904095f0bbf400
pdf-font-stream PDF embedded font (sfnt) at offset 0xE934 17660 bytes