Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5102b705beb1c63…

MALICIOUS

PDF

71.9 KB Created: 2021-07-02 17:28:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5ae352578cffc47d3571a395ae018ba8 SHA-1: 927c68de29e2ec4fd62f18b8a9fe3a64d44d105a SHA-256: b5102b705beb1c63cb00dc62cd3b54de1b07d0455f8743655126be5216591fd8
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress sites. This suggests the document is designed to lure users to potentially malicious or phishing websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9907

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://unionzglobal.com/ckupload/files/79514993448.pdf
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/0dae223d54283c8cad29d455bf1496f5/10501446106.pdf
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609580d21cc9d---92090345537.pdf
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcea73bf2a5---foxobubipugom.pdf
    • http://csptech.net/admin/userfiles/file/2805608350.pdf
    • http://locthanhwindow.com/img_duhoc/files/domavoremufubuxag.pdf
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/c1e699b052a3c132e05fe88929d5a055/91278809444.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160b61a77332cf---23957858074.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/32b2d788ac017f663d08e68e212db581/57184059281.pdf
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/52048327643.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160badac67b45b---30591938741.pdf
    • https://magerp.org/upload/files/duvojujagekabeko.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160769f9994430---kaliko.pdf
    • http://cosonhuath.com/hinhanh_fckeditor/file/tuwinagewedarerewoxojela.pdf
    • http://alliance-ltd.com/userfiles/volakijokoki.pdf
    • http://stihoplet.by/upload/editor/files/zexud.pdf
    • http://am-assets.com/aom/magnolia/userfiles/file/bivuvu.pdf
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/f3dd256c604d8fb82e68d692b9704231/fipofelipazijopawaziti.pdf
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b08fb0522fc---bororabefilivu.pdf
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/masopilovozasewun.pdf
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b75a54c71dc---96080484106.pdf
    • http://sowitech.vn/upload/files/46318782346.pdf
    • https://majubesar.com/contents//files/25431878703.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/ovtkgs3q6qn0i3rfbqq9gpdosr/84198447525.pdf
    • https://nhaccugiare24h.com/uploads/userfiles/file/92498051360.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/669e71cab6b350213a61bf2cd698dff7/41194530425.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=ps%2B+free+trial+code
    • 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_off0000ba4d.bin
1ec4e730ca33075badd35446550241b4e7c1da3557cf1313a4a6a66317532add
pdf-font-stream PDF embedded font (sfnt) at offset 0xBA4D 15228 bytes
font_01_sfnt_off0000e13e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE13E 16792 bytes
font_02_sfnt_off0000f955.bin
a64b6f2168f9c9cb0d3d136ad459e90be2555d1c98524f3a308e0b2f50dff5dd
pdf-font-stream PDF embedded font (sfnt) at offset 0xF955 10368 bytes