Malicious PDF — malware analysis report

Static analysis result for SHA-256 e16e4364758d2998…

MALICIOUS

PDF

106.8 KB Created: 2021-08-23 09:42:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a130cc0da8df9350ce1df95c7e6ae8ea SHA-1: 20ce98fe3b875da068b05d6f17eaf89c3f9e93aa SHA-256: e16e4364758d29989b3f8f3af5a4e640608eef04e8d2d1bbf595b31deaf365d6
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript and numerous external URIs pointing to other PDF files hosted on compromised websites, suggesting a phishing or malware distribution campaign. The presence of a link farm on disposable hosting and links pointing to compromised CMS upload storage further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9866

Heuristics 8

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://infrive.ru/uplcv?utm_term=dlse+paid+sick+leave+posting
    • http://hersheyhigh1981.com/clients/37302/File/52765665748.pdf
    • http://petukmahaaaraj.com/userfiles/file/rixanolasu.pdf
    • http://fiumevivo.it/userfiles/files/13756894573.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/ec5ff09ac0a898ed10caf69e053be0af/94440420474.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/lkpnv1i8unq70162tqhfropul0/30481390398.pdf
    • http://sacoorhealth.pt/site/upload/file/pazovapepamolo.pdf
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/686dc5ee748cf04f58f96b7d34250180/66224979957.pdf
    • https://theatresaucinema.fr/uploads/file/zonezarajuta.pdf
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/3d1b8794822b363ae4ff8ccca6c98297/tikefalenetopiwutonij.pdf
    • http://mpu-beratung-brendle.de/userfiles/file/33860992503.pdf
    • http://meyergarden.com/ckfinder/userfiles/files/tuxolotawilinawa.pdf
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/depukixexi.pdf
    • http://2m-m.eu/userfiles/files/livibetipomozi.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/5fahsqa7kg5bpjs2qethf1agh5/71600369296.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160804b7682279---55409280120.pdf
    • http://mkbeauty.vn/luutru/files/75233564587.pdf
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1611607a445d53---pizeta.pdf
    • http://oilandgaswork.com/userfiles/file/sereja.pdf
    • https://contabil-fiscal.ro/mm/file/74595303017.pdf
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/31618e2bb3fa8df2d05e4ad067660f63/fexiganiserudolufa.pdf
    • https://mclandpin.com/calisma2/files/uploads/natanovezixisesodulu.pdf
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a97951d2ec---xiturak.pdf
    • https://www.bankkartya.hu/js/ckfinder/userfiles/files/26641906183.pdf
    • http://lightningriskassessment.com/ci/userfiles/files/29268755706.pdf
    • https://pnp-studio.com/fckeditorfiles/file/80150142519.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb0b2a8560---99701456554.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_off00013de4.bin
e9db4252203fd4add5c568eeebf3ed69462b2a0a8d9821bd371da926b255c803
pdf-font-stream PDF embedded font (sfnt) at offset 0x13DE4 17372 bytes
font_01_sfnt_off00016b52.bin
e5dc07b6655a33628e6e9163c3f1be234e3bff8c9ec55e3afc769be10dccef55
pdf-font-stream PDF embedded font (sfnt) at offset 0x16B52 10748 bytes
font_02_sfnt_off000183ff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x183FF 16792 bytes