Malicious PDF — malware analysis report

Static analysis result for SHA-256 d581b67099cec602…

MALICIOUS

PDF

81.4 KB Created: 2021-09-04 23:23:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 67c267ae41bd519cfa78214ebc936c7a SHA-1: 5f67d5f35cd423058f76495b9721b5a550fefc00 SHA-256: d581b67099cec602407a2b92a485fc537915e15682850e9f2075097a928a701a
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and the use of UTM parameters in some URLs further support the link farm and potential phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bbccf018f3b---xejumesudunugelubitok.pdf In PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070d37601e50---33718976273.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/files/73158530725.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/161029c24c5e73---jewobiwoliwibiraxonusovo.pdfIn PDF document text
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/15ec1b479b35cc3f03f569571afb199e/sijefugataweti.pdfIn PDF document text
    • http://arkystudio.eu/userfiles/files/zidiworarum.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160890b26924ee---tiforadejawimede.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161050f19370a3---70696228395.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608835ee12605---miwukodajo.pdfIn PDF document text
    • https://huaienclinic.com/uploadpic/files/wejefur.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/59599839630.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/b7bf0478445f80db3f32d61ef15e4b46/52648073725.pdfIn PDF document text
    • https://dwitunggaljaya.com/sitefiles/file/27681089951.pdfIn PDF document text
    • https://tjpapigroup3.com/contents//files/7941869871.pdfIn PDF document text
    • http://toonesk.com/upload/51575226605.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/99948658108.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/v6mf4dheafeotk5kc541g2apr3/bulijular.pdfIn PDF document text
    • https://die-elke.de/cms/elke_page_files/file/453043446.pdfIn PDF document text
    • http://stellamaris.cz/userfiles/80896648052.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/xezunoj.pdfIn PDF document text
    • http://heninrealty.com/userfiles/files/41649189504.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=nursing+process+and+critical+thinking+pdfPDF 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_off0000da86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA86 17244 bytes
SHA-256: d0251c7938e8df553f6af08e58351a1b37179b346273a8dc7a974ac80c3950a3
font_01_sfnt_off000106c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011edf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EDF 11068 bytes
SHA-256: df572812297cf00235f7b5e371790da89f0addbbbf6e07163c59631cc0ed3613