Malicious PDF — malware analysis report

Static analysis result for SHA-256 c70552723abcd550…

MALICIOUS

PDF

77.5 KB Created: 2021-07-17 11:15:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0652ab00104ea92f9a0266df5f56fed9 SHA-1: 80f8aabe15e7c06e8e5bb027e84d824a959e95fd SHA-256: c70552723abcd5508cbc51a677dcec5f49c8a6c0b655afb52992951044ea2ebc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the link farm and the PDF's structure suggest it is intended to lure users to external malicious sites, likely as part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://stasta.com/userfiles/file/kijesudofikaru.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098a4b7c0d8c---9159362099.pdf
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/16i192vli1984p7tib1gseeekl/wazakuzomirevuzibiwililor.pdf
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/12445e95eb270618f395fed35367a257/8277926883.pdf
    • http://jncs.kr/page_data/file/20210713054250.pdf
    • https://www.phuketvillarentalandservices.com/ckfinder/userfiles/files/nifiwowosisovak.pdf
    • http://tareeapartment.com/user_img/files/21326095315.pdf
    • http://crediramasrl.it/public/file/93995340655.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b2ed4b231b4---64722213976.pdf
    • http://iseveranscopy.com/upload/editor/file/64087255726.pdf
    • http://ahsaipu.com/v15/Upload/file/202151313945307.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/13181162891.pdf
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/b3a6b0c1d38f29360d25e33a43e725d8/sibelagibikojorej.pdf
    • http://watsonwilliamsreunion.com/clients/82103/File/2693532583.pdf
    • http://wildpflanzen-planung.de/file/8007266637.pdf
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/030db10644731c616ca5c4560d7a1945/5041157508.pdf
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/1609ed08c105f1---91031862257.pdf
    • http://amandamaitland.com/images/file/mowetujexat.pdf
    • https://geneolock.com/locktactyuma/userfiles/file/kerozuve.pdf
    • https://www.comperat-89.fr/ckfinder/userfiles/files/54022524948.pdf
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b767f03eb---bunem.pdf
    • http://africanhairbraidingsalon.com/userfiles/file/74173367677.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16080f27cc0aa9---dotevupudemiregiv.pdf
    • http://skonasystems.com/userfiles/file/5307100199.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=excision+of+a+lung
    • 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_off0000cefa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEFA 16792 bytes
font_01_sfnt_off0000e70c.bin
19dc5415c8a092bdf464890d09d4960282de79e792ef12e855b0ae69ff03ee58
pdf-font-stream PDF embedded font (sfnt) at offset 0xE70C 16372 bytes
font_02_sfnt_off00011186.bin
42bc02f8e6ba38005598cf5691ebb201a492c753a9bc2455fd1931ab50f38fed
pdf-font-stream PDF embedded font (sfnt) at offset 0x11186 10368 bytes