Malicious PDF — malware analysis report

Static analysis result for SHA-256 42c3056a360a6fbf…

MALICIOUS

PDF

98.1 KB Created: 2021-08-02 21:44:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9a57743c4f55ab197e57f9e6a3cd3923 SHA-1: 826d565deb38ae54c463a83a31770f075998356e SHA-256: 42c3056a360a6fbf8ebe6eb5b1a6749bd809b6b1fb8ababe824dc74a5052db67
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, many of which are hosted on compromised CMS uploads or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://internationalmedia.com/userfiles/file/kugekivolefidovelepuf.pdf
    • http://cu-hinothai.com/ckfinder/userfiles/files/44206819243.pdf
    • http://immobilieninvestors.de/userfiles/file/56865132693.pdf
    • http://adamlegal.com/userfiles/file/mijufanazisudurikeju.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cac49a50452---10354721193.pdf
    • http://koryosushi.com/uploads/files/kakulivodafunagiwo.pdf
    • https://veterinarycarefoundation.org/userfiles/file/xofuzafumededepubilofa.pdf
    • http://chretkinia.pl/userfiles/file/22094031679.pdf
    • https://everestart.com/images/stories/file/bomedujetomulasazogoruvag.pdf
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160c171ce8c024---27201770614.pdf
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/9e5df454975a7a2b552331a18ee33f2c/tegonixepizowu.pdf
    • http://alnadaoil.com/userfiles/file/nexitep.pdf
    • http://dztechfin.com/upload/file///31273914405.pdf
    • http://www.tomasjelinek.com/img/pub/file/rapuw.pdf
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075424dd573d---sigilobejubavugowaporuvad.pdf
    • http://kodemari.info/data/files/zurijinitelakadujigap.pdf
    • https://artlabjo.com/userfiles/file/xekafafesodojixepu.pdf
    • https://economiadecomunion.com/ckfinder/userfiles/files/womugaluxupatajopojas.pdf
    • https://alarouba.com/ckfinder/userfiles/files/83461895184.pdf
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160c25012daa2c---19238377161.pdf
    • http://classicalgardenornaments.com/uplds/file/wagokukesegegutowa.pdf
    • https://fotobolfestmeny.hu/mvc/userfiles/file/11492748700.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=para+que+sirve+el+geslutin+pnm
    • 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_off00011673.bin
4c0526fe081125e3004c9192bd15a7f46c69190f4180b09f5525cfb639ad4119
pdf-font-stream PDF embedded font (sfnt) at offset 0x11673 10788 bytes
font_01_sfnt_off00012ef7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EF7 16792 bytes
font_02_sfnt_off00014709.bin
95af9c65b26c8fd953b5289315c3ae3f53ce41c34060938d264ea53397a39953
pdf-font-stream PDF embedded font (sfnt) at offset 0x14709 19136 bytes