Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad1576f38a913ced…

MALICIOUS

PDF

68.4 KB Created: 2021-09-12 12:44:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b5a2cbec03f554ff36c7b34215e49ab1 SHA-1: 7e0a2d360d8bba155dabb57367cf0189cf338bc5 SHA-256: ad1576f38a913ced90a074b16bf3725111e00ac1aae42e49e75a20e48237004b
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent. No scripts were extracted, but the structure and URL distribution are indicative of a downloader or redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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://scpt.it/userfiles/files/43547517517.pdf In PDF document text
    • http://www.fred-robin.com/ckfinder/userfiles/files/61430574446.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c9ffeae885---51177824516.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/03fdb4b93d00ab0c8752c9159b53e907/35454779316.pdfIn PDF document text
    • http://kanizsakran.hu/userfiles/file/xuvokufidajiwawupeg.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/68167827410.pdfIn PDF document text
    • http://snnet.kr/board_pds/fckeditor/2021/09/file/46842834471.pdfIn PDF document text
    • http://euroear.eu/ckfinder/userfiles/files/kozevomuk.pdfIn PDF document text
    • https://citronel.com/userfiles/files/numasagofoletu.pdfIn PDF document text
    • http://metallpress.ru/files/91605164723.pdfIn PDF document text
    • http://www.gabrielamaciel.net/images/content/file/wekarujurowe.pdfIn PDF document text
    • http://skmsm.com/userData/board/file/lunitotukevelasunokuk.pdfIn PDF document text
    • http://yizhu580.com/ckfinder/userfiles/files/gosipakadu.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/50838192664.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/savuzukibokagutagijalevi.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210901100050_cepn9m.pdfIn PDF document text
    • http://hagelkonzept.de/userfiles/file/34957012961.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/tm3krt5nc8dblvq7pjnv9tqec4/24400757506.pdfIn PDF document text
    • http://alexdisinfestazioni.com/userfiles/files/82808024612.pdfIn PDF document text
    • https://hongmao.tw/uploads/files/202109031637115886.pdfIn PDF document text
    • http://iamsong.vn/uploads/files/fubotuderofezovaku.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/wojoxalexatonutefe.pdfIn PDF document text
    • https://medicabg.com/uploads/wysiwyg/files/sajelatazoxilibib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=dok+chart+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_off0000b016.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB016 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c82d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC82D 10268 bytes
SHA-256: 13474d9ea36c4e9c0c0a23888400409a89d223d6d3706205aeb6fe2c835c6d5e
font_02_sfnt_off0000df6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF6C 14844 bytes
SHA-256: 3d1e26c51b5227a6e666a6be6d5831429630854a47847463df30205963097c0d