Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4e201719c7a9610…

MALICIOUS

PDF

83.3 KB Created: 2021-09-06 20:06:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b4d3b3870b219d810f51b1c846e70a0a SHA-1: 85868ca2f167336bb18621f9ac3c747fc0fc4ab9 SHA-256: b4e201719c7a961074c717fae0d89a1ede37e54fd4103433ea1798b061d51565
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 CMS upload directories, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL analysis are sufficient to infer the attack pattern.

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 http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16091323eb4742---zepinumatami.pdf In PDF document text
    • http://esistore.lu/userfiles/file/15206015769.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/kogori.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/af78ddeb27baae02b10ead14eb3601a4/ferisububamose.pdfIn PDF document text
    • http://hockeydh.com/files/ups/files/jugoj.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16078fd094cbc1---93392696019.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609890dd3ffd7---20794360159.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/113e53f00b7602e730c3bd8415a8dd5b/36350971947.pdfIn PDF document text
    • http://akpanlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/73777562233.pdfIn PDF document text
    • https://quangtriasianwindow.com/uploads/image/files/75888760223.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/83hmhk541a9bvv0g4so0mkij21/42442842448.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aecf6516e87---36521565090.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/92841325425.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16090d9bbafce0---46974149447.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/9bf4a56178b0f68fbf272db8bae29050/6341262904.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee56282061---puzikitivalugiruves.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/gajakikisemusevowotapope.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160c0c657687aa---moziroxetopizori.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/sorejemafavuwij.pdfIn PDF document text
    • http://www.trackls.com/application/ckeditor/ckfinder/userfiles/files/rilonisa.pdfIn PDF document text
    • https://gtselect.fr/ckfinder/userfiles/files/71905629162.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=two+step+equations+math+worksheetPDF 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_off0000e055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE055 17864 bytes
SHA-256: d362ad6abd7388b2ce7b0f4525ce0ffb4d4d0d3697804c23df05a57279c3fb4c
font_01_sfnt_off00010e7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012693.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12693 10860 bytes
SHA-256: 263d409785e89e16bba8825818c5614b660c04fa199660a41441f13bad84a965