Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4c9eee2f5086175…

MALICIOUS

PDF

78.5 KB Created: 2021-08-26 13:29:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: bd5421a3c280ce9082ba483a2784ab51 SHA-1: 15408f2a44b2064f5efd3e8337901a8e17c2eb15 SHA-256: c4c9eee2f50861758cea04e64d3b265b1b370cd405c298c4c0ee838546544723
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The presence of numerous external URIs, including links to compromised CMS uploads and disposable hosting, indicates a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated content rather than user-readable text, further supporting a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://pistant.ru/uplcv?utm_term=10+foot+pounds+to+inch+pounds PDF link annotation
    • http://hsound.ro/images/custom/file/35167555610.pdfIn PDF document text
    • https://perfecthospital.net/FCKeditor/file/4759575266.pdfIn PDF document text
    • https://caribemed.com/userfiles/file/kudugosigulerubipaboliv.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d16d175a54---tekelisudolevegixetubapir.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9112175a28---fajukibol.pdfIn PDF document text
    • http://dorinhawear.com/admin/fckeditor/editor/filemanager/connectors/php/fckeditor/editor/filemanager/connectors/php/userfiles/file/71200685440.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/duzuzatisomenabivoruse.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/32262172585.pdfIn PDF document text
    • https://landbondcorten.com/attachment/file/d9224c871b206ffa128fbc1e1020e697.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/ea8f5bd5a858985845070e109bf30a94/68179799574.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/812c0a1d05519d2a84df1b64ec1add43/96210242788.pdfIn PDF document text
    • https://bandotrading.com/uploads/file/mokibo.pdfIn PDF document text
    • https://copperscraphandlers.com/ckfinder/userfiles/files/wusanazufeluzozuvaxi.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611732255dda4---bomozabamite.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/kawuzagevigekitiro.pdfIn PDF document text
    • https://ikansambel.com/contents//files/jixifenopi.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/96679f6e18c8ca6f19a96e18258e3125/98570057626.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a38406162f4---deradazejopava.pdfIn PDF document text
    • http://xn--72c7caerxx0d3a9eve.com/UserFiles/File/zuvurusigorinepoxiba.pdfIn PDF document text
    • https://apc-algercentre.dz/ckfinder/userfiles/files/34774179739.pdfIn PDF document text
    • http://lamelove-zakryti.cz/userfiles/file/lumujodogibosafatizok.pdfIn PDF document text
    • http://thebellingerfamily.com/clients/0/05/05034faaa501c69409a7459485cba135/File/gojafarizegu.pdfIn PDF document text
    • http://cphs1970.net/clients/877309/File/tijavoxubufeturifuti.pdfIn PDF document text
    • http://yngc.ru/admin/ckfinder/userfiles/files/sexapijigopavibu.pdfIn PDF document text
    • https://wagaskar.com/media/97651873203.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d2f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB04 16188 bytes
SHA-256: 96bbbb3dc36cc2a054357bc084d1f3930ea7cb6e12458cdc39a45917f117ee34
font_02_sfnt_off000114cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CC 10452 bytes
SHA-256: 30f8e8d993ceef591cb2d845a80f46dc14cc0f434c3d17f79d1a94840625e115