Malicious PDF — malware analysis report

Static analysis result for SHA-256 494d1c6706731b5c…

MALICIOUS

PDF

87.4 KB Created: 2021-09-02 13:55:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e679d0db973613e49fc46a9f03061aad SHA-1: b5327e4191d765004ce0c80695393dd982156046 SHA-256: 494d1c6706731b5c51bf90587c175c1d152e1a33e5a9f67df70f8cef1add082d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1190 Exploit Public-Facing Application

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and a high-confidence ML classifier. It contains numerous links pointing to compromised WordPress sites, suggesting it's part of a phishing or malware distribution campaign. The presence of link farms on disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/4618722b8ac0e0d698c8ed7577a3d541/28153594091.pdf In PDF document text
    • https://lanhcongnghiepthinhphat.com/upload/files/95149952970.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/04a1c5bdff22e90d377b6ae78f3b6a58/57751446150.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160905e146b866---20195558035.pdfIn PDF document text
    • http://www.taimaobi.com/admin/ckfinder/userfiles/files/40717729067.pdfIn PDF document text
    • http://hibertek.com/image/files/20210627_205104.pdfIn PDF document text
    • http://opuspoint.com/ckfinder/userfiles/files/tawokuwol.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/7175112884.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/88139882638.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a5867b6a9af---26311528510.pdfIn PDF document text
    • https://clarkfamilybuilders.com/home/clark/public_html/ckfinder/userfiles/files/zelaxozezajikenudejob.pdfIn PDF document text
    • https://lesfeesdelhetre.fr/upload/files/54554554949.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/90655d2d8c7c6cf62ba1082b35d749d5/34619001183.pdfIn PDF document text
    • https://vmgeducationtrust.org/home/vmgedu/public_html/public/userfiles/file/lebazinifidiseka.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bac6fb45722---wotozadisobelileto.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606de14075f24---rodemegape.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/pixanasadotep.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a0ae8a0485d---79844817028.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/e13870f3f92c21218fd1ebc12bdae195/43088553834.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608c663916a57---fotadima.pdfIn PDF document text
    • http://93564497.com/userfiles/98878844672.pdfIn PDF document text
    • http://www.kymenhome-etsinta.net/tiedostot/files/vadijadebigira.pdfIn PDF document text
    • http://marketherballize.com/ckfinder/userfiles/files/pedebuv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=char+broil+big+easy+owners+manualPDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/pijal.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_off0000ef20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF20 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010732.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10732 18352 bytes
SHA-256: f4dc02e74533edeab10eb17640d7e04272120f5078e0cd8400132ffad386df95
font_02_sfnt_off0001366f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1366F 10928 bytes
SHA-256: 8a8e77f1337539cdf3dac978d41cd272b98d064d4ddd57d0f62e7c672b25f048