Malicious PDF — malware analysis report

Static analysis result for SHA-256 63f22e39c4460ac2…

MALICIOUS

PDF

74.5 KB Created: 2021-08-28 14:53:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1be1de1cb4630c2149a7668bccc17ce3 SHA-1: e3b312b66f292b9c6593452dd04009410dac20d2 SHA-256: 63f22e39c4460ac2dc94eb8461379cdb00baa28097dd66038f35a1deb831cfef
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of external URIs and compromised CMS upload links points to a coordinated effort to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://ketchas.ru/uplcv?utm_term=another+word+for+hard+of+hearing
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb7d3f0c6f---24869975245.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7fcae515f---28595840251.pdf
    • http://sushrutproctology.org/ckfinder/userfiles/files/vijevilal.pdf
    • http://kondicionery-noginsk.ru/upload_picture/file/40768914945.pdf
    • https://meganimal.pt/site/upload/file/81447180062.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d5d09dc8b12---fevazekivodakulusa.pdf
    • http://anhuifan.com/upload_fck/file/2021-8-5/20210805210943745264.pdf
    • http://beloezoloto.ru/userfiles/file/45471537825.pdf
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8766db9509---rivubur.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/10d591020e274ad19a08ce8e8dac5326/1282308737.pdf
    • http://apexibd.com/uploads/fck_uploads/file/doraxumorudeja.pdf
    • http://www.sudaff.com/pics/file/jetuwetesatix.pdf
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ba06392845f---42442038765.pdf
    • http://thuocnam.xyz/images/files/16215240631.pdf
    • http://canphantich.net/Images_upload/files/nitorowenugonikabazofa.pdf
    • https://walnutcreekguide.com/wysiwygfiles/file/gamafexiwuxesitabesabe.pdf
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c2adceb4999---48843313931.pdf
    • https://pima-alarms.net/slicice/file/nogebatitopobafili.pdf
    • https://cplastik.com/data/cms/file/rovanidurevadizajisoro.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/454e7a306cbf857aa22879cfbca0745f/15086930664.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/9580dd71ac96e3500f9b1a794cde4ae5/9050069625.pdf
    • http://ducthanggroup.com/webroot/img/files/22931139324.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_off0000c12b.bin
773a5d3399e50edf21279d816933c14fcc341b1cd37678f46327a0880ca38709
pdf-font-stream PDF embedded font (sfnt) at offset 0xC12B 10484 bytes
font_01_sfnt_off0000d8d1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D1 16792 bytes
font_02_sfnt_off0000f0e3.bin
2b6c3f17e9a0a94df6e252b3dc283c3952aac9adab24d88f3bffd1f9c2df15c6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E3 16624 bytes