Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c3cfe5d58f58b17…

MALICIOUS

PDF

80.9 KB Created: 2021-09-21 19:43:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 543ebe861c1b6a8edb4fdc11684a71f5 SHA-1: 79889196a3aafeade444bd8fb62cab6bb84d6379 SHA-256: 1c3cfe5d58f58b17f92138484f84c70a0f42ded6240e238820ed593fd4e13d23
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised websites or disposable domains, indicating a link farm designed to lure users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://aftp.bg/userfiles/file/gatabuf.pdf
    • http://delve-cr.com/uploads/66089392827.pdf
    • https://morethancars.eu/uploads/edytor/file/kemomenixolimilitebat.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613630e00b623---61967361869.pdf
    • http://fashioneducation.ru/userfiles/file/lefalokexobofewesobaja.pdf
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nebevexakisare.pdf
    • http://www.grupoaccs.net/ckfinder/userfiles/files/bolajipenufakibelufe.pdf
    • https://108pizza.pl/uploads/userfiles/files/28640175207.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16142ab03b9fb1---75357280836.pdf
    • http://www.sname.org.tw/sname/ckfinder/userfiles/files/4531142790.pdf
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/cc5e315d3095902143adfd31ee68317e/fivojoz.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16148e452485f2---tobaginitomi.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/161436aa06caed---pemarisiratikomuti.pdf
    • https://rubin2000-distribuitorshop.ro/userfiles/file/63615929380.pdf
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/11927818685.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16139ea03335e1---88843711789.pdf
    • http://sibstroiexp.ru/userfiles/file/99077315048.pdf
    • https://dehaventransportation.com/home/de/public_html/ckfinder/userfiles/files/30654543956.pdf
    • http://w-f-l.de/user_img/file/39673404842.pdf
    • https://tybistanbul.org/resimler/files/dawisovenonifudu.pdf
    • http://weilandensemble.nl/ckfinder/userfiles/files/43706403677.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=left+4+dead+2+download+android+apk
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b8d3.bin
5b88e9db20a8f473247b82b2d0ce330631deec1f99e183d15031f6a24b8230bc
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8D3 21792 bytes
font_01_sfnt_off0000ef55.bin
6ec0a307146d9be2bdd9dd9a35227856c774c3cce985d3f038f6c9b4f02e256a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF55 16080 bytes
font_02_sfnt_off00010488.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10488 16792 bytes
font_03_sfnt_off00011c9f.bin
94cac5446672bc91dec6229b16b3a2a1ea7c08fcff88afae03815e839693835b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C9F 10656 bytes