Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac49377ab4bb8e78…

MALICIOUS

PDF

81.8 KB Created: 2021-06-28 07:58:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b9b931a3b6cbe0d795540f69304f6a25 SHA-1: 9996cb146afa1df008e0a77761426ef18ee2a983 SHA-256: ac49377ab4bb8e78297aff2c506fb325a7796593688083adc04f26ae86784562
156 Risk Score

Malware Insights

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

The file is a PDF containing a link farm hosted on multiple compromised WordPress sites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The URLs point to PDF files within formcraft plugin upload directories, suggesting a common method for hosting malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a46f68d59ed---39872615894.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9208a423dc---latinobegowababaw.pdf
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160802e1d89208---bizexipuworabutapodo.pdf
    • https://corpusbg.com/files/fck/file/18743832357.pdf
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a331e28bcec---lakafa.pdf
    • http://thesnowmanicecream.com/ckfinder/userfiles/files/feroxisiriwupivetapilaw.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160b0f09c7de7d---38068342421.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/a9fe99e498524909ee4d2fa462ef6069/6444430842.pdf
    • http://goodslib.com/userfiles/files/35981756507.pdf
    • http://anhbanglaw.com/userfiles/file/73394947419.pdf
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/ec32c163d1a5c7e203c4482a8c5d248f/12131227794.pdf
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/e997473c18926c5b0dcedc3c4ca663c8/83666881705.pdf
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8c72a33932---zonuzuxako.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca81fc3dc4---94248519211.pdf
    • http://chixue.com/uploadfile/file/20210604094626.pdf
    • http://sllight.ru/design/img/upload/file/63386083779.pdf
    • http://fatamorgana.fr/uploads/assets/file/29094153541.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc0aeb45f4---12219932070.pdf
    • https://publicbridge.pl/userfiles/file/fudegadagis.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bc7d294ba42---67582739492.pdf
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/onv1irun70ap78im73t13g4417/53379852426.pdf
    • http://unityproductions.com/upload/files/86181270703.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=add+subtract+multiply+divide+integers
    • 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_off0000dcbc.bin
f880640577f4b3ffcf0e384d007601be43c0cc8c2509f286c1d589d818d453c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCBC 16724 bytes
font_01_sfnt_off00010869.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10869 16792 bytes
font_02_sfnt_off00012080.bin
bc1f963706d40021409186a2991f2d6aa6e089df8764036f6d047fddc94f4f73
pdf-font-stream PDF embedded font (sfnt) at offset 0x12080 11140 bytes