Malicious PDF — malware analysis report

Static analysis result for SHA-256 63a31caec503eb4e…

MALICIOUS

PDF

95.6 KB Created: 2021-07-31 01:28:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: eefe60a849f1313a22cf714b73d86b3f SHA-1: 62ac4de8513b20ea3290c296a3cea4c071c912c7 SHA-256: 63a31caec503eb4ea9b231f242d71dc6d5d5a5a5f927da813af7b56af554c266
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised websites or disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The file's structure as a link farm is a common tactic to obscure the ultimate destination and evade initial detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://medvor.ru/uplcv?utm_term=can+can%27t+must+mustn%27t+have+to+don%27t+have+to+exercises+pdf PDF link annotation
    • http://dobrejaja.com/Upload/file/walexadiliwijet.pdfIn PDF document text
    • https://club-sports.net/uploads/products/files/23562390161.pdfIn PDF document text
    • http://studiomistretta.com/userfiles/files/zolitinufigojutudowawiru.pdfIn PDF document text
    • http://chsjackets75.com/clients/a/ae/ae1e0d6431e3080ad3d3eb1024a27f31/File/87254175043.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/ltt23tl44ol0104led8ahj0uth/siwij.pdfIn PDF document text
    • http://architetturaurbanistica.it/userfiles/files/14278613309.pdfIn PDF document text
    • http://mya1fc.com/files/ckuploads/files/xamawaliroze.pdfIn PDF document text
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/cje4l34taorpmu21jqbluhn7ko/maxowasijuz.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f9f77cedd---mujul.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609a11085d648---94670511194.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/64311917c61d60c8a1805b36e3e18f8b/94479766244.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/25074744823.pdfIn PDF document text
    • https://aplusadvance.com/naver_editor/data/file/27457645632.pdfIn PDF document text
    • http://phutungvespaco.com/luutru/files/89776276395.pdfIn PDF document text
    • http://armanetti.com/images/vozajujekixilikesumumo.pdfIn PDF document text
    • http://studioego.cz/userfiles/file/48222253433.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bbc23216ee---vixixitire.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160abccb00d81b---7645220790.pdfIn PDF document text
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/ba2c976ba39f64fd747399043c12ccbe/gafebobor.pdfIn PDF document text
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608c89a1aec34---78076772072.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16079a7ab474c3---88591987883.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/4bdb72831b82127ad5ee568da0c40cb0/nilasovejizulufa.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/fop5nd5m6j52s5n81993k7ps90/mazaxosimu.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_off00010e3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E3E 17832 bytes
SHA-256: fb8182302bdf1dff55f0257a8c5e1eb422a2cf6b21f7fc8d71429a6332deb0e4
font_01_sfnt_off00013d23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D23 11172 bytes
SHA-256: c1ba007b14a9c35e330efb20ae8a4197a7663e40efcebea983cc4dc4c4a8a42d
font_02_sfnt_off00015734.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15734 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1