Malicious PDF — malware analysis report

Static analysis result for SHA-256 bdfb2696ba521e50…

MALICIOUS

PDF

82.1 KB Created: 2021-09-24 04:01:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3993551ff5fb559d18d8925f0a110ee2 SHA-1: c922f09cdbdb7e1e4078030ead4fce2c7f201bc1 SHA-256: bdfb2696ba521e50adfa5e5fa3a61511fbf012b4a992023ebf3440f76fcc5abf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous URLs, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to potentially malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to distribute second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://irlanc.ru/uplcv?utm_term=android+text+messaging+skins
    • http://appartenvue.net/appart/upload/images/83885947452.pdf
    • http://csc-0411.com/userfiles/file/20210914170954_s3y5m5.pdf
    • https://brs.jo/userfiles/files/7161419715.pdf
    • http://soluzionebenessere.eu/userfiles/files/zokaronojegejavi.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b7603cfac---39040968164.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d0ec6ca286---vuluwegifez.pdf
    • https://cortopolis.ar/userfiles/file/71184043025.pdf
    • https://skvely-kup.cz/files/file/16269846509.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e210bd1a33---tikokiruxenatil.pdf
    • https://cantarefides.ro/admin/userfiles/file/27974061309.pdf
    • http://abaj.cz/UserFiles/File/sobutuxobi.pdf
    • https://agronlogistics.com/userfiles/files/21539596141.pdf
    • http://polyalpan.hu/_user/file/989798627.pdf
    • http://www.autoservis-hubatka.cz/admin/upload/ww/file/60337007906.pdf
    • https://asfus.net/virgsurv/userfiles/file/kawonazesapanizededuma.pdf
    • http://xy-interior.com/uploads/files/202109191101094039.pdf
    • http://feldbach-tourismus.at/files/33918128787.pdf
    • https://mangonebike.com/uploads/file/14800125146.pdf
    • https://dsverano.com/UserFiles/File/porapegobuxofumutivamilu.pdf
    • https://aordonez.com/images/contenidos/files/83116701235.pdf
    • https://ever-progress.com/upload/files/pivaluwube.pdf
    • https://isigakizima.net/img/tmp/file/37608863714.pdf
    • http://vietcem.vn/public/default/ckeditor/files/68691309113.pdf
    • http://kammed.com/userfiles/file/lituwofad.pdf
    • http://rintoyo.com/userfiles/file/fudadadutakopazikox.pdf
    • https://travelworld.ro/userfiles/file/4050970163.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db6a.bin
ddd4a6836b50f73179483fca65f4b439b91ee1c1ca50b376ed1a51fd2c67c1d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB6A 10720 bytes
font_01_sfnt_off0000f3e1.bin
cfbcfd3085d493bf0a12c3f764388bca09cfaa4fb2b51239948eedfefc63f86b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3E1 18252 bytes
font_02_sfnt_off000122ac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x122AC 16792 bytes