Malicious PDF — malware analysis report

Static analysis result for SHA-256 31268c3e550975eb…

MALICIOUS

PDF

71.0 KB Created: 2021-09-23 03:03:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3fc2bd7c770407dcb1df8533cb74e033 SHA-1: 5738d4f95b64d42effc8988673c159581fd9d714 SHA-256: 31268c3e550975ebb6029a0a37bd82a9e86756e0fcdf8c913e35d3aad17f6bca
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to suspicious domains and are part of a link farm, suggesting a phishing or malware distribution scheme. The PDF structure and embedded content are consistent with attempts to exploit vulnerabilities or trick users into downloading further malicious content.

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://alltimescare.com/attachment/files/90213514516.pdf In PDF document text
    • https://alves.bg/ckfinder/userfiles/files/wolomarokobudezurutuxuk.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210903_025003.pdfIn PDF document text
    • https://www.agcontraincendios.es/ckfinder/userfiles/files/doxikafaxidelodefinipeter.pdfIn PDF document text
    • http://lex.tj/img/file/63324455050.pdfIn PDF document text
    • http://usairsprings.com/userfiles/file/mojozezuz.pdfIn PDF document text
    • http://american-security-inc.com/assets/ckfinder/userfiles/files/46315123944.pdfIn PDF document text
    • http://netmutum.com/userfiles/file/57095125534.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210922201545803.pdfIn PDF document text
    • http://hophungvietnam.com/app/webroot/uploads/files/38594437687.pdfIn PDF document text
    • http://tsg-edinstvo.ru/userfiles/file/70531178478.pdfIn PDF document text
    • http://year-c.com/upload_fck/file/2021-9-19/20210919030030605742.pdfIn PDF document text
    • http://miyagi.chi-kara.net/Upload/files/soxinajumebasesogusitaga.pdfIn PDF document text
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/delumilekuwamupusakovu.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138e8a66f744---zelitowowevemol.pdfIn PDF document text
    • http://stadion-zarya.ru/ckfinder/userfiles/files/54244925827.pdfIn PDF document text
    • https://nepalfinepashmina.com/userfiles/file/86400767554.pdfIn PDF document text
    • http://opuspointpartner.com/ckfinder/userfiles/files/31167780830.pdfIn PDF document text
    • http://tuzoltosagmihald.hu/userfiles/file/99573069212.pdfIn PDF document text
    • http://hndgyl.com/v15/Upload/file/2021991928298319.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.info/upload/files/62283043525.pdfIn PDF document text
    • http://netmutum.com/userfiles/file/45032234189.pdfIn PDF document text
    • http://holidayinntorino.com/userfiles/files/piturena.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613d834a55811---fovixaro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=games+like+final+fantasy+tactics+on+pcPDF 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_off0000b40e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB40E 10784 bytes
SHA-256: 061876a36e9aa8480e08c6c2868224aae9809e6640305a4965cebcc1e6ca68aa
font_01_sfnt_off0000ccf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE506 16336 bytes
SHA-256: 8f9295b739d60d8946293a9e2d4441b66dffdbbfeb7b04b04c4d093b8e39024d