Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c9d3f5dc96f600e…

MALICIOUS

PDF

85.2 KB Created: 2021-06-28 13:21:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1c42a9d4cc771f6654340cc7d65799b5 SHA-1: b530538854b26c10d9ae1973fc4bd20780ca6c5e SHA-256: 3c9d3f5dc96f600e4362d3c506c1064ede99aaf88d8bae57a497b8da802df222
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a phishing or malicious redirection attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious content or exploit kits. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://allnatureint.com/userfiles/file/10117479618.pdf In PDF document text
    • http://claphamtaxi.com/survey/userfiles/files/94932458855.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/82824c6d935234cb01e2e05705e665b5/22694520488.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b46c975f9e1---digesimomuzida.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc9573b511---gagukudowezepitazilofilo.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160735c97caa91---29816662487.pdfIn PDF document text
    • http://rocb-ap.org/file_media/file_image/file/62471492108.pdfIn PDF document text
    • http://babamoleskine.com/files/file/wozazugafajujonoweraro.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088388eca6b4---refuwujiduwemisu.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cc6666bbffd---4735676103.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160785ab52ee58---81995207621.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/16096f155d7b45---74744259783.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ae5f5de7b00---pisurivepominifegifiwixe.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a758746da0---32683373165.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c247a802a08---12823677452.pdfIn PDF document text
    • https://mfdesign.hu/files/file/mujaziguxafuzogodabo.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607130f97e36c---totobuvegur.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bda7226fde7---91943698820.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609299b76a0b1---17719007448.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d569e5b905---65378065383.pdfIn PDF document text
    • http://gptools.net/userfiles/file/koduwabowerulagolewopapep.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091055672dc7---vetapovisofarin.pdfIn PDF document text
    • http://mobilesamara.com/img/files/file/56835226686.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160c7554bbb7bf---pawazirisakuxolopitenopa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=or+fester+like+a+sore+and+then+runPDF 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_off0000e969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE969 17688 bytes
SHA-256: 64f4674d4c072004fdf57be653ebc1f1ca1569b6b7f9a9376410ad394b405c8f
font_01_sfnt_off00011712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11712 10668 bytes
SHA-256: fc0a75d3fd704468b8a0e35f5b64d386b60191ec3343537e30862d2f9a9c46a1
font_02_sfnt_off00012f77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F77 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1