Malicious PDF — malware analysis report

Static analysis result for SHA-256 f525892dea455c06…

MALICIOUS

PDF

76.8 KB Created: 2021-08-25 12:27:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 7d862f3c4f22e30b0fc5b4f3af801661 SHA-1: 70c6ccd1fe7ffe4cf498db64333bf07fa26b5cca SHA-256: f525892dea455c0600183aafe708ab6f8f2165b0bdcf382f64cc6d7ac18e37cb
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to compromised WordPress sites and disposable hosting. The primary goal appears to be directing users to malicious external resources, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://anhbanglaw.com/userfiles/file/nawubora.pdf In PDF document text
    • http://www.johnrealestate.in/ckeditor-ckfinder-integration/uploads/files/56892615091.pdfIn PDF document text
    • https://springkasteelhuren.be/userfiles/file/kexedozukipo.pdfIn PDF document text
    • http://allycatering.com/userfiles/debixinoduzibanu.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160900a4b0ade5---347567383.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089fe3020be9---65226991217.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160943cf331380---fafuvitipukopoxemedodime.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a0ce2b02a47---49298279459.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/tirijudarud.pdfIn PDF document text
    • http://korvet-sp.ru/userfiles/file/gurozoxilugenu.pdfIn PDF document text
    • http://dorinhawear.com/admin/fckeditor/editor/filemanager/connectors/php/fckeditor/editor/filemanager/connectors/php/userfiles/file/80223596315.pdfIn PDF document text
    • http://2017.letnifestiwal.pl/ckfinder/userfiles/files/53723130358.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/tivadowowosidulituxaje.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021080313070373499.pdfIn PDF document text
    • http://zeci.nl/im/image/58068853612.pdfIn PDF document text
    • http://ydis.kr/userfiles/file/251155535871.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c52bb47a4b1---wufexuxewakosukonamuvagar.pdfIn PDF document text
    • http://www.hermosabeachbungalows.com/userfiles/files/ruvemejijedasupogogirata.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/16530689aa35025af226e5fcfffa8673/melukavumupajafasotudasa.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/e053imcgakeaga31ujedgl5dm0/fovuwupo.pdfIn PDF document text
    • http://pronobile.de/catalog/file/pemorenabiketesobad.pdfIn PDF document text
    • http://logo4you.dk/userfiles/file/47631406610.pdfIn PDF document text
    • http://iucecb.com/files/file/wadasiwepasunixu.pdfIn PDF document text
    • http://www.dilipprabhavalkar.com/images/file/43610385720.pdfIn PDF document text
    • http://bydnjl.com/userfiles/files/6939726699.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/64163949697.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5007e6146---tirexifasiwefizot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=modded+3ds+gamesPDF link annotation
    • 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_off0000cbb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBB2 10316 bytes
SHA-256: 5511e78f2ca2e660c2f4324773b6f851d189e1e53b7f70145c49ef868ad19785
font_01_sfnt_off0000e2cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2CD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fadf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFADF 16444 bytes
SHA-256: b122ff35ad84e5bf65ad5459dfde31158c522b6396c406358fa9f000dadf3672