Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdc71116b3d10b89…

MALICIOUS

PDF

66.5 KB Created: 2021-07-13 18:54:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 64d2effaf72da88eb9eff734b981a5f0 SHA-1: 8da6406db0e3f673dfd81b0cb083c2ddb8972ba2 SHA-256: cdc71116b3d10b89d640c5d3f11ced54cba70898df6ec8dd22d940fb9c0b47d3
162 Risk Score

Malware Insights

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

The sample is a malicious PDF detected by ClamAV as a phishing trojan. It contains embedded JavaScript and a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites. The embedded JavaScript likely facilitates the redirection or exploitation process, while the link farm serves to obscure the ultimate destination and increase the chances of a successful compromise. The use of a link farm on compromised CMS uploads suggests an attempt to evade detection and leverage existing infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6960

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://laborke.ru/uplcv?utm_term=free+porn+games+on+ios PDF link annotation
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/a2aptbeoep98kp75bg2tqm2u6e/raviwerebefelafabesapus.pdfIn PDF document text
    • https://cochleartudaskozpont.hufiles/96464927842.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080467c26c1e---banuzodawabenezazufov.pdfIn PDF document text
    • https://bbpartner.cz/userfiles/file/35546746326.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072394d6ab49---jorolo.pdfIn PDF document text
    • https://asiajitutop.com/contents//files/99251928609.pdfIn PDF document text
    • http://apartamentosalbatros.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd216647402---sinixefige.pdfIn PDF document text
    • http://farashimirooz.com/files/4434290010.pdfIn PDF document text
    • http://lightningriskassessment.com/ci/userfiles/files/23410919706.pdfIn PDF document text
    • http://falconartistmanagement.com/ckfinder/userfiles/files/timaledoteliti.pdfIn PDF document text
    • https://alzubidi.com/userfiles/files/42382635485.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/35m2nkqagshhbg2n2mlm0ks0su/16638996773.pdfIn PDF document text
    • http://vintageguitar.ru/ckfinder/userfiles/files/dobirasigisuletuzapexuv.pdfIn PDF document text
    • http://morecoredesign.com/images/imageUps/files/gewujorigoditivawenu.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ec4494d031a---10629007327.pdfIn PDF document text
    • https://registracijakoncar.com/webroot/js/ckfinder/userfiles/files/zokasowatefaw.pdfIn PDF document text
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/totipitipa.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a397a5098b---xodopadivexaketavozat.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/f1ppgqgd6c3v1ou7i47jtv4avk/46076217933.pdfIn PDF document text
    • http://aligokdemir.com/resimler/files/95676367677.pdfIn PDF document text
    • https://ficsllc.com/wp-content/plugins/super-forms/uploads/php/files/arqcf1gd1ni9fs3tat4ctfvg2n/wolajigozigerofe.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cc96b94ef61---wegifukomotatumoru.pdfIn PDF document text
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/40930407120.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ebb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1