Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa0aa81f83cd5d1b…

MALICIOUS

PDF

88.8 KB Created: 2021-07-01 20:34:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 51245e7b01a52a8f4d640afdf28a7bd6 SHA-1: e6917e7e9f522eb8e86ef5ea03a911aa7e2f71d6 SHA-256: fa0aa81f83cd5d1b27439922a49c8213f117c9b69670eb41da0997691792f4dc
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a link farm pointing to multiple compromised WordPress sites, which in turn host further PDF documents. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of external URIs and link farms on compromised CMS uploads suggests an attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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.
  • 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
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://medvor.ru/uplcv?utm_term=water+shut+off+without+notice
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160869408e6eae---zuzovulusurerobipuzewag.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/tsdtnt9tr3ij7nbv23librj58o/welunimupixeropusedete.pdf
    • http://syarmarka.ru/userfiles/files/21746323009.pdf
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/7afc0db69f0a876a8a7de86f18911489/zuxenokiwafipij.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a33e9d9cecd---tevabafavexinekol.pdf
    • http://architects-desk.com/uploadsfile/10068174588.pdf
    • http://apexibd.com/uploads/fck_uploads/file/mukunufawowererasirevun.pdf
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/lhmdnf1an5n1f4mbo7kekj8037/waselizekalufixikor.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b8c13a6c53d---xalozadokuzalekupave.pdf
    • http://jatyn.cn/upfiles/202105/file/1620822861.pdf
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b57231334c---xebajevudolaralemanamij.pdf
    • https://ringid.vn/ckfinder/userfiles/files/zatofofezitup.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a89263067---28726045270.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdf55f0ef50---9427055310.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/3f4f605a51445cc737dfa9c859feee46/32909649449.pdf
    • https://sy-tech.eu/file/32549359405.pdf
    • http://beiwendq.com/userfiles/file/93563698571.pdf
    • http://liddellgaryfamily.com/clients/863293/File/67747061132.pdf
    • http://www.tobywells.org/media/fckdir/file/39917252697.pdf
    • http://wallsfamilyreunion.com/clients/876683/File/20929105022.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac3aa5844be---39023372619.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16074d27e96739---vovifasazodotomaxigug.pdf
    • https://angelsstaff.com/uploads/file/87475254473.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160bcd561da6d9---10336763011.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_off0000f889.bin
b8f35850c4914e41f846597e39bc8cb92a2a9dba592a07804a2e2f52486d880c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF889 16764 bytes
font_01_sfnt_off0001242c.bin
0c801b6275d0f13957e4bd09402267110d8817df514cc93f986700a4f8cc3f0c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1242C 10568 bytes
font_02_sfnt_off00013c59.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C59 16792 bytes